Template:is-ndecl

Declension of akur (masculine)

	singular		plural
	indefinite	definite	indefinite	definite
nominative	akur	akurinn	akrar	akrarnir
accusative	akur	akurinn	akra	akrana
dative	akri	akrinum	ökrum	ökrunum
genitive	akurs	akursins	akra	akranna

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The following documentation is located at Template:is-ndecl/documentation. ^[edit]

Useful links: subpage list • links • redirects • transclusions • errors (parser/module) • sandbox

Uses Lua:

• Module:is-noun

Basic usage

This template is used to generate a declension table for Icelandic nouns. Be careful using this template because Icelandic noun declension is very complex. If you are not completely sure about how a given noun is declined, check it against the declension tables at Beygingarlýsing íslensks nútímamáls (BÍN).

Examples

Page	Example	Comment
hestur (“horse”)	{{is-ndecl|m}}	Many nouns require only the gender to be specified (m, f or n for masculine, feminine or neuter, respectively).
	Declension of hestur (masculine) singular plural indefinite definite indefinite definite nominative hestur hesturinn hestar hestarnir accusative hest hestinn hesta hestana dative hesti hestinum hestum hestunum genitive hests hestsins hesta hestanna
arður (“profit”)	{{is-ndecl|m.sg}}	Example of a singular-only noun.
	Declension of arður (sg-only masculine) singular indefinite definite nominative arður arðurinn accusative arð arðinn dative arði arðinum genitive arðs arðsins
hófur (“hoof”)	{{is-ndecl|m.dati/-}}	Most strong masculine nouns ending in a single consonant require an override that specifies the dative singular because it is highly unpredictable. The format is dat followed directly by the indefinite and definite endings, respectively, separated by a slash. Here, the indefinite ending is -i and the definite ending (before the definite clitic -num) is null; i.e. indefinite hófi, definite hófnum.
	Declension of hófur (masculine) singular plural indefinite definite indefinite definite nominative hófur hófurinn hófar hófarnir accusative hóf hófinn hófa hófana dative hófi hófnum hófum hófunum genitive hófs hófsins hófa hófanna
baugur (“ring”)	{{is-ndecl|m.dati:-/-:i}}	If there is more than one possibility for the dative, separate them by a colon and list them in order of commonness (refer to BÍN for this information).
	Declension of baugur (masculine) singular plural indefinite definite indefinite definite nominative baugur baugurinn baugar baugarnir accusative baug bauginn bauga baugana dative baugi, baug baugnum, bauginum baugum baugunum genitive baugs baugsins bauga bauganna
höfundur (“author”)	{{is-ndecl|m,ar}}	If the genitive singular ending is not -s (for masculine or neuter nouns) or -ar (for feminine nouns), specify it following the gender, separated by a comma.
	Declension of höfundur (masculine) singular plural indefinite definite indefinite definite nominative höfundur höfundurinn höfundar höfundarnir accusative höfund höfundinn höfunda höfundana dative höfundi höfundinum höfundum höfundunum genitive höfundar höfundarins höfunda höfundanna
vindur (“wind”)	{{is-ndecl|m,s:ar[rare]}}	As with dative overrides, if there are two possibilities for the genitive singular, separate them with a colon. Use square brackets after an ending to specify a footnote.
	Declension of vindur (masculine) singular plural indefinite definite indefinite definite nominative vindur vindurinn vindar vindarnir accusative vind vindinn vinda vindana dative vindi vindinum vindum vindunum genitive vinds, vindar1 vindsins, vindarins1 vinda vindanna 1Rare.
þröskuldur (“threshold”)	{{is-ndecl|m,s:ar,ar:ir}}	If the nominative plural ending is not -ar (for masculine nouns) or -ir (for feminine nouns), specify it following the genitive singular override. Here, there are two possibilities -s and -ar for the genitive singular, and two possibilities -ar and -ir for the nominative plural. The accusative plural is automatically derived from the nominative plural; see #Overrides following the gender spec below.
	Declension of þröskuldur (masculine) singular plural indefinite definite indefinite definite nominative þröskuldur þröskuldurinn þröskuldar, þröskuldir þröskuldarnir, þröskuldirnir accusative þröskuld þröskuldinn þröskulda, þröskuldi þröskuldana, þröskuldina dative þröskuldi þröskuldinum þröskuldum þröskuldunum genitive þröskulds, þröskuldar þröskuldsins, þröskuldarins þröskulda þröskuldanna
blundur (“slumber, doze”)	{{is-ndecl|m,,ir}}	To override the nominative plural but not the genitive singular, leave the latter blank.
	Declension of blundur (masculine) singular plural indefinite definite indefinite definite nominative blundur blundurinn blundir blundirnir accusative blund blundinn blundi blundina dative blundi blundinum blundum blundunum genitive blunds blundsins blunda blundanna
bifur (“beaver”)	{{is-ndecl|m.#}}	Use # to indicate that the -ur ending is part of the stem. This automatically enables stem contraction before vowel-initial endings and defaults the dative singular to -i.
	Declension of bifur (masculine) singular plural indefinite definite indefinite definite nominative bifur bifurinn bifrar bifrarnir accusative bifur bifurinn bifra bifrana dative bifri bifrinum bifrum bifrunum genitive bifurs bifursins bifra bifranna
nár (“corpse”)	{{is-ndecl|m,,ir}}	Nouns in -ár and -ær form the stem by default by dropping the -r. Use # if the -r is part of the stem.
	Declension of nár (masculine) singular plural indefinite definite indefinite definite nominative nár nárinn náir náirnir accusative ná náinn nái náina dative ná nánum náum náunum genitive nás násins náa náanna
bjór (“beer”)	{{is-ndecl|m}}	Nouns ending in -r that do not end in -ur, -ár or -ær include the -r in the stem by default. Use ## if the -r is not part of the stem.
	Declension of bjór (masculine) singular plural indefinite definite indefinite definite nominative bjór bjórinn bjórar bjórarnir accusative bjór bjórinn bjóra bjórana dative bjór bjórnum bjórum bjórunum genitive bjórs bjórsins bjóra bjóranna
bíll (“car”)	{{is-ndecl|m}}	Nouns in -ll and -nn drop the final consonant to form the stem. Use # to prevent this (e.g. with moll (“minor (in music); minor key”)).
	Declension of bíll (masculine) singular plural indefinite definite indefinite definite nominative bíll bíllinn bílar bílarnir accusative bíl bílinn bíla bílana dative bíl bílnum bílum bílunum genitive bíls bílsins bíla bílanna
gaffall (“fork”)	{{is-ndecl|m}}	Nouns in -all/-ill/-ull and -ann/-inn/-unn have stem contraction by default before vowel-initial endings. Note also that u-mutation is the dative plural (to göfflum) is automatically handled.
	Declension of gaffall (masculine) singular plural indefinite definite indefinite definite nominative gaffall gaffallinn gafflar gafflarnir accusative gaffal gaffalinn gaffla gafflana dative gaffli gafflinum göfflum göfflunum genitive gaffals gaffalsins gaffla gafflanna
kórall (“coral”)	{{is-ndecl|m.-con}}	Use con to force stem contraction where it is not the default, and -con (as in this case) to turn it off where it is the default.
	Declension of kórall (masculine) singular plural indefinite definite indefinite definite nominative kórall kórallinn kóralar kóralarnir accusative kóral kóralinn kórala kóralana dative kóral kóralnum kórölum kórölunum genitive kórals kóralsins kórala kóralanna
blástur (“breeze, wind”)	{{is-ndecl|m.#.imut}}	Nouns with i-mutation before endings beginning with an i should use imut to signal this. (Here, # indicates that the -ur ending is part of the stem; see above.)
	Declension of blástur (masculine) singular plural indefinite definite indefinite definite nominative blástur blásturinn blástrar blástrarnir accusative blástur blásturinn blástra blástrana dative blæstri blæstrinum blástrum blástrunum genitive blásturs blástursins blástra blástranna
böllur (“ball”)	{{is-ndecl|m,ar,ir.unumut.imut}}	Nouns that were u-stems in Proto-Germanic have u-mutation in the lemma (nominative singular) form that must be reversed to obtain the stem. Use unumut to signal this. (These nouns also typically have irregular genitive singular -ar, irregular nominative plural -ir and i-mutation.)
	Declension of böllur (masculine) singular plural indefinite definite indefinite definite nominative böllur böllurinn bellir bellirnir accusative böll böllinn belli bellina dative belli bellinum böllum böllunum genitive ballar ballarins balla ballanna

Parameters

Normally there is only one parameter to specify. At the minimum, this must specify the gender: m, f or n for masculine, feminine or neuter, respectively, e.g. for hestur (“horse”):

{{is-ndecl|m}}

which produces

Declension of hestur (masculine)

	singular		plural
	indefinite	definite	indefinite	definite
nominative	hestur	hesturinn	hestar	hestarnir
accusative	hest	hestinn	hesta	hestana
dative	hesti	hestinum	hestum	hestunum
genitive	hests	hestsins	hesta	hestanna

Sometimes additional properties, or indicators, need to be specified to correctly inflect a given noun. An example is arfur (“inheritance”), which is singular-only:

{{is-ndecl|m.sg}}

which produces

Declension of arfur (sg-only masculine)

	singular
	indefinite	definite
nominative	arfur	arfurinn
accusative	arf	arfinn
dative	arfi	arfinum
genitive	arfs	arfsins

It is generally not necessary to explicitly specify any property that can automatically be inferred. For example, it is not necessary to specify whether a noun is strong or weak (this can be inferred from the noun's ending in the lemma form); nor is it usually necessary to specify that nouns like hattur (“hat”) have u-mutation in forms such as the dative plural (in this case, to höttum).

As shown, multiple indicators are separated by a dot (.). Most indicators can come in any order; exceptions are the indicators for gender, which normally must come first, and the adj indicator specifying that the term in question is an adjective, which likewise normally must come first. (If you need to combine adj with a gender, put adj first.) There are a lot of different indicators, and it's helpful to divide them into types. It is recommended that the following order be used when multiple indicators are required:

1. Gender (must come first)
2. Genitive-singular and nominative/accusative-plural overrides (must come directly after the gender, comma-separated)
3. Number
4. Definiteness
5. Stem indicators # and ##
6. Control specs (i.e. mutation, infix and contraction indicators), in whatever order seems most logical
7. Stem overrides (stem:..., vstem:..., etc.) and declension overrides (decllemma:..., declgender:..., declnumber:...)
8. Misc boolean indicators
9. Specific form overrides

The following sections discuss the recognized indicators in detail.

Gender, number, definiteness, common vs. proper

• Gender: m for masculine, f for feminine, n for neuter. In most cases, this must be given, and when given, it must come first. (All other indicators may come in any order, and are mostly optional.)
• Number: sg for singular-only nouns, pl for plural-only nouns, both for nouns with both singular and plural. If unspecified, the defaults are as follows:
  1. Proper nouns default to singular-only. The rules for determining a proper noun are:
     1. If the indicator common or dem is present, the noun is common (not proper).
     2. If the indicator proper is present, the noun is proper.
     3. If the invoking template is {{is-noun}}, the noun is common, and if the invoking template is {{is-proper noun}}, the noun is proper. (This normally only applies to indeclinable nouns, which specify the declension directly in the call to that template. Most nouns should use {{is-noun|@@}} or {{is-proper noun|@@}} to scrape the declension of an associated call to {{is-ndecl}}, which has no common/proper default.)
     4. If the noun begins with an uppercase letter followed by a lowercase letter, the noun is proper. (This rule is phrased this way to exclude abbreviations like DKS (“DNA”).)
  2. Otherwise, masculine nouns in -skapur or -naður default to singular-only.
  3. Otherwise, nouns default to both singular and plural.
• Definiteness: indef for indefinite-only nouns, def for definite-only nouns, bothdef for nouns that can be both indefinite and definite. Proper nouns (see just above for how this is determined) default to indefinite-only; all others default to both indefinite and definite.
• Common vs. proper: proper forces a proper noun (defaults to indefinite-only, singular-only), common forces a common noun (defaults to indefinite and definite, singular and plural), dem indicates a demonym such as Bandaríkjamaður (“American”) or Indónesi (“Indonesian”) (currently has the same effect as common).

Overrides

Overrides, per their name, allow you to override individual case/number forms. Overrides can be specified in two ways: directly following the gender spec and as separate indicators. The former type let you override the genitive singular and/or nominative and accusative plural, while the latter type let you override any case/number form. Both types use exactly the same format.

Overrides following the gender spec

The most commonly used overrides are those that follow the gender spec. The genitive singular ending is specified after the gender, separated by a comma, and the nominative plural ending follows, separated again by a comma. For example, for feldur (“fur; fur coat”), use:

{{is-ndecl|m,ar,ir}}

which indicates that the genitive singular should end in -ar and the nominative plural in -ir, and produces

Declension of feldur (masculine)

	singular		plural
	indefinite	definite	indefinite	definite
nominative	feldur	feldurinn	feldir	feldirnir
accusative	feld	feldinn	feldi	feldina
dative	feldi	feldinum	feldum	feldunum
genitive	feldar	feldarins	felda	feldanna

For most masculine nouns, the default genitive is -s and the default nominative plural is -ar, so both need to be overridden. Note that overriding the nominative plural in this fashion automatically overrides the accusative plural as well, which becomes -i, according to the following rules:

1. Feminines and neuters use the same ending for the accusative plural as is specified for the nominative plural.
2. Masculines drop the final -r from the ending to form the accusative plural ending unless the ending is -ur (possibly preceded by an i-mutation signal ^; see below), in which case the ending remains unchanged.

It should be noted that the specified endings are attached to the stem, not to the lemma. Generally the stem is correctly computed automatically from the lemma by dropping certain endings, e.g. -ur, -a or -i, as well as -l in a masculine lemma ending in -ll and -n in a masculine lemma ending in -nn. Sometimes a little help is needed, e.g. through the stem indicators # and ##, documented below.

If only the genitive singular needs to be overridden, leave off the nominative plural override and preceding comma, as with höfundur (“author”):

{{is-ndecl|m,ar}}

which produces

Declension of höfundur (masculine)

	singular		plural
	indefinite	definite	indefinite	definite
nominative	höfundur	höfundurinn	höfundar	höfundarnir
accusative	höfund	höfundinn	höfunda	höfundana
dative	höfundi	höfundinum	höfundum	höfundunum
genitive	höfundar	höfundarins	höfunda	höfundanna

If only the nominative/accusative plural needs to be overridden, leave the genitive singular override blank but keep the preceding and following comma, as with feminine skeið (“spoon”):

{{is-ndecl|f,,ar}}

which produces

Declension of skeið (feminine)

	singular		plural
	indefinite	definite	indefinite	definite
nominative	skeið	skeiðin	skeiðar	skeiðarnar
accusative	skeið	skeiðina	skeiðar	skeiðarnar
dative	skeið	skeiðinni	skeiðum	skeiðunum
genitive	skeiðar	skeiðarinnar	skeiða	skeiðanna

The general format for an override is a colon-separated list of endings, each of which can be followed by a footnote in square brackets. An example is snjór (“snow”) with various possible genitive singulars and nominative plurals, some of which are dated:

{{is-ndecl|m,s:var[dated]:ar,ar:var[dated].##}}

which produces

Declension of snjór (masculine)

	singular		plural
	indefinite	definite	indefinite	definite
nominative	snjór	snjórinn	snjóar, snjóvar1	snjóarnir, snjóvarnir1
accusative	snjó	snjóinn	snjóa, snjóva1	snjóana, snjóvana1
dative	snjó	snjónum	snjóum	snjóunum
genitive	snjós, snjóvar1, snjóar	snjósins, snjóvarins1, snjóarins	snjóa	snjóanna

¹Dated.

Here, three genitive singular endings are given and two nominative plural endings (which will accordingly generate two accusative plural endings with the -r dropped and the footnote maintained). If the same footnote is specified in more than one place, as here, they are deduplicated and only one footnote will appear at the bottom of the table. (The ## indicator is required to get a stem snjó- instead of snjór-, which would be the default for nouns in -ór.)

To specify an override consisting of an empty ending, use -. This occurs fairly frequently with proper nouns specifying place names, which often do not follow standard declension patterns, instead opting to be indeclinable or semi-indeclinable. An example is the feminine noun Madríd (“Madrid”), which frequently has a null-ending genitive (making the noun indeclinable), in addition to a normal genitive in -ar. Specify the following:

{{is-ndecl|f,-:ar}}

which produces

Declension of Madríd (sg-only feminine)

indefinite singular
nominative	Madríd
accusative	Madríd
dative	Madríd
genitive	Madríd, Madrídar

Note here that no nominative plural override is given, and in fact doing so triggers an error, because this noun is singular-only (and indefinite-only) and has no plural. (This is because the noun is identified as a proper noun by the initial capital letter. See #Gender, number, definiteness above for more information.)

Use -- to indicate that a given form is missing completely. This rarely needs to be given, but an example that requires it is völ (“choice”), which is singular-only and missing the genitive singular. Specify the following:

{{is-ndecl|f,--.sg}}

which produces

Declension of völ (sg-only feminine)

	singular
	indefinite	definite
nominative	völ	völin
accusative	völ	völina
dative	völ	völinni
genitive	—	—

Overrides may be preceded by ^ to force i-mutation of the preceding stem. An example of this is bók (“book”), with nominative plural bækur. Specify the following:

{{is-ndecl|f,,^ur}}

which produces

Declension of bók (feminine)

	singular		plural
	indefinite	definite	indefinite	definite
nominative	bók	bókin	bækur	bækurnar
accusative	bók	bókina	bækur	bækurnar
dative	bók	bókinni	bókum	bókunum
genitive	bókar	bókarinnar	bóka	bókanna

This is described in more detail in the section below on i-mutation.

In some cases, it is necessary to specify the full form in an override. To do this, specify the full value and precede it with an exclamation point (!). An example of this is nátt (“night”), with nominative/accusative plural nætur. The ending spec ^ur would not work here because it would result in nættur with the t still doubled. Specify the following:

{{is-ndecl|f,,!nætur}}

which produces

Declension of nátt (feminine)

	singular		plural
	indefinite	definite	indefinite	definite
nominative	nátt	náttin	nætur	næturnar
accusative	nátt	náttina	nætur	næturnar
dative	nátt	náttinni	náttum	náttunum
genitive	náttar	náttarinnar	nátta	náttanna

If you look at the tables produced in the presence of overrides, you'll notice that although the specified override ending is that of the indefinite form of the case/number combination, the definite form is affected likewise. Sometimes it is necessary to control the indefinite and definite endings separately. To do this, specify two override specs separated by a slash (/), both in indefinite form. An example where this is necessary is ell (“the letter L”), which has indefinite genitive singular either ell or ells, but definite genitive singular only ellsins. Specify the following:

{{is-ndecl|n,-:s/s.dat-:i/i}}

which produces

Declension of ell (neuter)

	singular		plural
	indefinite	definite	indefinite	definite
nominative	ell	ellið	ell	ellin
accusative	ell	ellið	ell	ellin
dative	ell, elli	ellinu	ellum	ellunum
genitive	ell, ells	ellsins	ella	ellanna

Note that overrides to the right of the slash (which control only the definite form) still need to take the form of an indefinite ending; the clitic is automatically added onto the specified ending. (The dat-:i/i is an example of an arbitrary case/number override, in this case for the dative singular. This override also takes the form of a two-part slash-separated spec, which is in fact extremely common with dative singular overrides. See the next section for more informaiton.)

Full-form overrides preceded by ! can also appear in two-part (slash-separated) specs, and as with ending overrides, take the indefinite form regardless of which side of the slash they appear on. An example is feminine brún (“brow”) (note, there is a different feminine word brún (“rim”) with a different declension):

{{is-ndecl|f,,ir:^[in fixed expressions]:!brýr[colloquial]/ir:^[literary]:!brýr[colloquial]}}

which produces

Declension of brún (feminine)

	singular		plural
	indefinite	definite	indefinite	definite
nominative	brún	brúnin	brúnir, brýn1, brýr2	brúnirnar, brýnnar3, brýrnar2
accusative	brún	brúnina	brúnir, brýn1, brýr2	brúnirnar, brýnnar3, brýrnar2
dative	brún	brúninni	brúnum	brúnunum
genitive	brúnar	brúnarinnar	brúna	brúnanna

¹In fixed expressions.
²Colloquial.
³Literary.

Here, the nominative/accusative plural expression is complex, with each of the two slash-separated specs specifying the same three possible forms (brúnir, brýn and colloquial brýr) but with differing footnotes. The definite forms automatically have the definite clitic -nar added onto the resulting form overrides, producing definite brúnirnar, brýnnar and brýrnar respectively.

Arbitrary overrides

You can also override an arbitrary case/number combination. This takes the form of a regular indicator, which can appear anywhere in the overall inflection spec. An override indicator looks like dati, which specifies that the dative singular takes an -i ending; or genplna, which specifies that the genitive plural takes a -na ending; or a more complex spec such as dat-:i/i given above, which specifies that the indefinite dative singular takes either a null ending or -i ending, while the definite dative singular takes only an -i ending (before the definite clitic is added). The important thing to notice is that the case/number spec (a lone case abbreviation nom, acc, dat or gen for singular slots, and a case abbreviation followed by pl for plural slots) is followed directly by the overriding ending(s), without any intervening delimiter. (If two slots take the same override value, you can combine them by putting a + between the slot specifiers, e.g. acc+datu to specify the both accusative and dative singular take -u, as with many female given names such as Sólveig. More complex specs can be given as well, such as acc+dat-:i:u for Berglind, which specifies that the accusative and dative singular take either a null ending, -i or -u.) Note that an override of the nominative plural specified in this fashion overrides only the nominative plural and does not affect the accusative plural.

Default genitive singular and nominative plural

To know whether to use a genitive singular or nominative plural override, it's important to know what the defaults are. The following table shows them. This table may seem a bit overwhelming at first. Focus on the endings of most strong nouns (the first row listed for each gender) and look up the others as necessary. (Weak nouns rarely need either the genitive singular or nominative plural overridden, although many weak feminine and neuter nouns need the genitive plural overridden, using e.g. genplna to specify that the ending is -na instead of -a.)

Gender	Type	Example	Genitive singular	Nominative plural
masculine	most strong nouns	hestur (“horse”)	-s	-ar
	nouns in -ir (which is not part of the stem)	læknir (“doctor, MD”)	-is	-ar
	nouns in -skapur (which default to singular-only)	vinskapur (“friendship”)	-ar	-ar
	nouns in -naður (which default to singular-only)	þjófnaður (“theft”)	-ar	-ir
	weak nouns in -i	tími (“time, hour”)	-a	-ar
	weak nouns in -a	herra (“gentleman; Mr.”)	-a	-ar
	nouns in -andi and -jandi	eigandi (“owner”), flytjandi (“performer”)	-a	-ur with i-mutation to e
	r-stem nouns	bróðir (“brother”)	-ur	-ur with i-mutation
feminine	most strong nouns	braut (“path, way”)	-ar	-ir
	nouns in -ur	hildur (“fight, battle”)	-ar	-ir
	nouns in -ing	eining (“unit”)	-ar	-ar
	nouns in -ung	nauðung (“constraint; compulsion”)	-ar	-ar
	nouns in -i	keppni (“competition, match”)	-i	-ar
	nouns in -á (which forms part of the stem)	á (“river”)	-r	-r
	nouns in -ó (which forms part of the stem)	kónguló (“spider”)	-ar	-r with i-mutation (to æ)
	nouns in -ú (which forms part of the stem)	trú (“belief”)	-ar	-r
	weak nouns (in -a)	saga (“story; history; saga”)	-u	-ur
	nouns in long i-mutated vowel + -r (stem ends in the unmutated vowel)	kýr (“cow”), sýr (“sow”), ær (“ewe”) and compounds	r with i-mutation back to the lemma vowel
	r-stem nouns	móðir (“mother”)	-ur	-ur with i-mutation
neuter	most strong nouns	land (“land”)	-s	null ending with u-mutation
	nouns in -i (which is not part of the stem)	kvæði (“poem, song”)	-is	-i
	nouns in -é (which is not part of the stem) with .já indicator	tré (“tree”), fé (“sheep; cattle; money”)	-és (but fé has genitive in -jár)	-é
	weak nouns (in -a)	hjarta (“heart”)	-a	-u

Default dative singular for masculine nouns

Under some circumstances, the dative singular of masculine nouns is largely predictable and has defaults that apply for most nouns. For other nouns, however, the dative singular is largely unpredictable, and an override must be supplied or an error results. The defaults are as follows:

Type	Indefinite default	Definite default
weak nouns	-a
nouns in -ndi	-a
nouns in -ir	-i
nouns in -skapur	null ending
nouns in -naður	-i	-i or null ending (both possibilities are given)
nouns in -kell	stem + -keli or stem + -katli (with footnote archaic)
nouns in -ó	null ending
r-stem nouns (.rstem)	-ur
nouns in -ingur or -ungur	-i	null ending
j-infix nouns (.j)	null ending
nouns whose stem ends in two consonants (except -kk or -pp)	-i
nouns in -x	-i
contracted nouns (.con, -ur with .# specified, or in -all/-ill/-ull or -ann/-inn/-unn)	-i
proper nouns not ending in a vowel	-i
nouns in whose stem ends in a vowel or -r (other than contracted nouns)	null ending
nouns in -ll without contraction	null ending
nouns in -nn without contraction	-i
all others	override required

Approximately speaking, strong uncontracted common nouns whose stem ends in a single consonant (or -kk or -pp) need an override. This override must be two-part with a slash (e.g. dat-/i), because such nouns typically have different indefinite and definite endings.

Control specs

Control specs control various aspects of the declension. There are three types of control specs:

1. mutation specs (specifying how u-mutation works and whether i-mutation, reverse u-mutation and/or reverse i-mutation happen);
2. infixing specs (specifying whether a j or v is infixed between the stem and vowel-initial endings);
3. contraction specs (specifying whether contraction, i.e. deletion of the last stem vowel, occurs before vowel-initial endings).

What distinguishes control specs from other indicators is that multiple comma-separated values for a given spec type can be specified, and each can be given a footnote, which is attached to all forms affected by that spec. See examples below.

Mutation specs

Mutation specs control u-mutation (the change of a to ö or u); i-mutation (the change of a back vowel to a front vowel, such as a to e or á to æ); reverse u-mutation (the change of a u-mutated vowel ö or u back to a); and reverse i-mutation (the change of an i-mutated vowel back to its original vowel). In some cases, more than one mutation spec of a given type can be given, comma-separated. For example, umut,uUmut indicates that either regular u or double u/U-mutation can happen, leading to two possible outputs in circumstances where u-mutation applies (e.g. the dative plural). An example where this might be applicable is banani (“banana”), which has dative plural either banönum (regular u-mutation) or bönunum (double u/U-mutation). See examples below.

u-mutation

The following u-mutation specs exist:

• umut indicates that when u-mutation should happen (e.g. in the dative plural), it should be regular u-mutation (if the last vowel in the word is a, it changes to ö). This is the default in most circumstances, and does not normally need to be given. The exact circumstances in which u-mutation happens are not specified by this indicator (but are normally triggered by an ending beginning with u, and sometimes in other circumstances); only the type of u-mutation is indicated.
• uUmut indicates that the type of u-mutation should be double u/U-mutation (if the last vowel in a word is a, it changes to u, and if the second-to-last vowel is a, it changes to ö). This is the only common type of u-mutation in nouns other than regular u-mutation; the types below are rare.
• uumut indicates that the type of u-mutation should be double u/u-mutation (if either of the last two vowels in a word are a, they change to ö). This type of u-mutation is rare, but occurs for example as one of two types of u-mutation that occur in hafald (“heddle (in a loom)”) (producing nominative/accusative plural höföld and dative plural höföldum), along with regular u-mutation.
• Umut indicates that the type of u-mutation should be single U-mutation (if the last vowel in a word is a, it changes to u, and the second-to-last vowel is unaffected even if it's a). This type of u-mutation is rare and occurs mostly in its inverse, where sometimes you need to change u to a in the last syllable while leaving alone a preceding ö (examples are fjölgun (“increase”), örvun (“encouragement”), etc.).
• uUUmut indicates that the type of u-mutation should be triple u/U/U-mutation (if the last vowel in a word is a, it changes to u; if the second-to-last vowel is a, it also changes to u; and if the third-to-last vowel is a, it changes to ö). This type of u-mutation does not occur in nouns, but occurs fairly frequently in superlative adjectives (e.g. saltaðastur (“saltiest, most salty”), with feminine söltuðust). It is mentioned here for completeness.
• u_mut indicates that the type of u-mutation should be u/--mutation (if the second-to-last vowel in a word is a, it changes to ö; the last vowel is unaffected). This type of u-mutation is provided for completeness but has no known uses.

Note the following about u-mutation:

1. It does not affect au vowels. Hence, regardless of the type of u-mutation specified, the dative plural of naut (“bull”) is nautum, not #nöutum.
2. u-mutation "skips" over a final -ur ending. Thus, regular u-mutation applied to the neuter noun mastur (“mast”) produces nominative/accusative plural möstur; effectively, the final -ur is invisible.
3. u-mutation can be explicitly requested in an ending override by prefixing the override with ^^. It is rare that you will have to do this, but (e.g.) it is used internally when specifying the nominative/accusative plural ending of neuter nouns.

Reverse u-mutation

Reverse u-mutation is exactly like normal u-mutation but applies in reverse, i.e. ö and sometimes u vowels are converted to a rather than the other way around. This is used to derive the underlying stem from the lemma when the lemma itself has u-mutation applied, as with many feminine nouns (e.g. gjöf (“gift”)) and some masculine nouns (e.g. fjörður (“fjord”)). Feminine nouns in fact have regular reverse u-mutation as the default; thus gjöf will automatically have genitive singular gjafar without this needing to be explicitly specified.

The reverse u-mutation specs are exactly like normal u-mutation specs but are prefixed by un. Specifically:

• unumut indicates that regular reverse u-mutation should happen (if the last vowel in the word is ö, it changes to a). The circumstances under which this happens aren't specified by this indicator, but generally it occurs before endings that start with an a or i (unless i-mutation is also in effect, which takes precedence). For example, fjörður (“fjord”) needs unumut.imut to specify that regular reverse u-mutation to fjarð- happens e.g. in the genitive singular fjarðar, and i-mutation to firð- happens e.g. in the nominative plural firðir. Keep in mind that unumut is the default in some circumstances (as mentioned above), e.g. for feminine nouns with ö as the last stem vowel such as gjöf (“gift”) and sögn (“story, tale; verb”).
• unuUmut indicates that double reverse u/U-mutation should happen (if the last vowel in a word is u, it changes to a, and if the second-to-last vowel is ö, it also changes to a). The circumstances under which this happens aren't specified by this indicator and are different from those under which regular reverse u-mutation happens. For example, söfnuður (“congregration”) needs unuUmut, producing genitive singular safnaðar and genitive plural safnaða. The specific circumstances under which double reverse u/U-mutation takes place are: (a) for masculines, in the genitive singular and plural; (b) for feminines, in the nominative, accusative and genitive plural.
• unuumut, unUmut, unuUUmut and unu_mut are the reverse u-mutation indicators corresponding respectively to uumut, Umut, uUUmut and u_mut. These are mostly provided for completeness; but as indicated above, some nouns like fjölgun and örvun require unUmut because the u changes to a while the ö doesn't change. The circumstances under which these types of reverse u-mutation apply are the same as for unuUmut (and *NOT* the same as for unumut; see above).
• -unumut, -unuUmut, etc. explicitly disable reverse u-mutation. They differ from each other only when an associated footnote is provided (see below); the footnote is added to the forms where reverse u-mutation would take place, which differs between unumut and unuUmut (see above).

i-mutation

The following i-mutation specs exist:

• imut indicates that i-mutation should happen before endings beginning with i and wherever i-mutation is explicitly requested by prefixing an ending with ^ (see below).
• -imut indicates that i-mutation should not happen. This is normally used in conjunction with imut, and especially for hooking a footnote off of -imut; see examples below.

Note the following about i-mutation:

1. i-mutation can be explicitly requested in an ending override by prefixing the override with ^. This is useful, for example, when specifying the plural of nouns with i-mutation in their plural, such as bók (“book”), which requires a plural override ^ur to produce plural bækur. (Remember that this isn't necessary if the ending begins with i, provided that the imut spec is given. An example of where this is used is háttur (“way, manner; kind, type; habit”), which has i-mutation in the both the dative singular, with ending -i, and in the nominative plural, with ending -ir. The overall spec would look something like m,ar,ir.imut, indicating that (a) i-mutation applies; (b) the default genitive ending is -ar instead of default -s; (c) the plural ending is -ir instead of default -ar.)
2. The imutval:... indicator can be used to explicitly specify the vowel used in i-mutation. This is occasionally necessary. For example, sonur requires imutval:y since the default i-mutation of o is e not y.

Reverse i-mutation

Reverse i-mutation is exactly like normal i-mutation but applies in reverse. This is used to derive the underlying stem from the lemma when the lemma itself has i-mutation applied. Usually this applies to plural-only nouns with i-mutation in the nominative and accusative plural (but not in the dative or genitive plural), but it also applies to ketill (“kettle”) and a few related nouns, which have a dative singular without i-mutation (see below).

The reverse u-mutation specs are exactly like normal i-mutation specs but are prefixed by un. Specifically:

• unimut indicates that reverse i-mutation should happen in certain circumstances, which depend on the gender and number. Specifically: (a) masculine nouns have reverse i-mutation in the dative singular and throughout the plural, as with ketill (“kettle”) with dative singular katli; (b) feminine nouns have reverse i-mutation in the accusative and dative singular and the dative and genitive plural, as with kýr (“cow”) and ær (“ewe”). unimut is also used with i-mutated plural-only nouns that have some forms (generally the dative and genitive plural) without i-mutation, such as feminine hættur (“bedtime, quitting time”); feminine mætur (“appreciation, liking”); neuter læti (“behavior, demeanor”); and neuter ólæti (“noise, racket”).
• -unimut indicates that reverse i-mutation should not happen. This is normally used in conjunction with unimut, and especially for hooking a footnote off of -unimut; see examples below.

Note that, as for normal i-mutation, the specific resulting vowel can be controlled by imutval:.... (Here, the vowel specified is the resulting (non-mutated) vowel, not the source (mutated) vowel. For example, bætur (“compensation, benefits”) (plural only) requires imutval:ó, as the default reverse i-mutation vowel for æ is á.

Infixing specs

Infixing specs control the infixing of j or v after the stem and before certain endings. You do not need to (and in fact should not) specify an infixing spec when the lemma contains the infix in it, such as kirkja (“church”). As with mutation specs, in some cases more than one infixing spec of a given type can be given, comma-separated. For example, -j,j indicates that j-infixing either does not or does happen (respectively). See examples below.

The infixing specs recognized are:

• j to infix a j before endings that begin with a or u (not counting the lemma, which often has an ending -ur). An example where this is used is egg (“blade edge”), which has genitive singular and nominative plural eggjar, etc.
• -j turns off j-infixing. As mentioned above, this is normally used to indicate optional j-infixing.
• v to infix a v before endings that begin with a, i or u (not counting the lemma, which often has an ending -ur). An example where this is used is söngur (“song”), which has nominative plural söngvar, etc.
• -v turns off v-infixing. As mentioned above, this is normally used to indicate optional v-infixing.

Contraction specs

Contraction specs indicate whether contraction (deletion of a final-syllable a, i or u in the stem before a vowel-initial ending) should happen. As with mutation and infixing specs, in some cases more than one contraction spec of a given type can be given, comma-separated. For example, -con,con indicates that contraction either does not or does happen (respectively). See examples below. Note that contraction is the default is various cirumstances, and you will need to use -con to turn it off.

The contraction specs recognized are:

• con specifies that a final-syllable a, i or u in the stem (generally before single final r, l or n) is deleted before an ending beginning with a vowel. An example is gaffall (“fork”), whose stem gaffal- contracts to gaffl- before a vowel-initial ending such as dative singular gaffli, nominative plural gafflar and dative plural göfflum. (This latter form shows that u-mutation, and for that matter mutations in general, apply after contraction.) Contraction is in fact the default in masculine nouns ending in -all, -ill, -ull, -ann, -inn and -unn, as well as in masculine and neuter nouns ending in -ur that is part of the stem. (Final -ur is part of the stem by default in neuters, and in such a circumstance, definite contraction is also the default; see below. For masculines, final -ur is only part of the stem when the # indicator is given; see #Stem specs below.) An example of a noun that explicitly needs con is hamar (“hammer”), with contracted stem hamr- (dative plural hömrum).
• -con turns off contraction. This is useful when contraction is the default, as described above. Examples where this is needed are kórall (“coral”) and kristall (“crystal”), which never have contraction, and rafall (“generator”), which optionally has it (leading to dative plural either rafölum or röflum).
• defcon turns on definite contraction, which means that contraction also applies not only before a vowel-initial ending but before a vowel-initial definite clitic when the actual ending is null. For example, consider masculine akur (“field”) (cognate with English acre) and neuter mastur (“mast”). Both have contraction, leading respectively to dative singular akri and mastri. However, only mastur has definite contraction; contrast definite nominative singular akurinn vs. mastrið. As described above, the presence of definite contraction in neuters in -ur but not nominatives in -ur is the default, so in these cases, defcon doesn't have to be given explicitly. However, it does need to to be given for feminine fjöður (“feather”), which has both regular and definite contraction but where neither is the default; hence con.defcon needs to be specified.
• -defcon turns off definite contraction, either when it is the default or when used in conjunction with defcon to indicate a noun that either does or does not have definite contraction.

Stem specs

Masculine nouns usually (although not always) have an ending in the lemma form (indefinite nominative singular), and to compute the stem it's necessary to remove the ending. The following default rules are used to compute the stem of masculine nouns:

1. Nouns in -i and -a drop this suffix.
2. Nouns in -ur drop this suffix, as long as (a) the noun is not in -aur and (b) at least one vowel precedes or the term is a suffix (so that e.g. bur (“son”) does not drop -ur).
3. Nouns in -ir drop this suffix under similar conditions, i.e. as long as (a) the noun is not in -eir and (b) at least one vowel precedes or the term is a suffix.
4. Nouns in -ár and -ær (but not any other vowel followed by -r) drop the -r.
5. Nouns in -ll and -nn drop the last consonant.
6. All other nouns use the lemma as the stem.

Sometimes these result in incorrect stems. For example, akur (“field”) has stem akur- not ak- (likewise bifur (“beaver”), blástur (“breeze”) and several other terms in -ur); Bergmann and certain other names have a stem in -nn not -n; and contrariwise, terms like sjór (“sea”) and gnýr (“gnu; boom”) have stems without the final -r. The following indicators are available for these terms:

• # forces the stem to be the same as the lemma. Hence akur, bifur, Bergmann, etc. use {{is-ndecl|m.#}}.
• ## forces the stem to not include final -r or (if present) -ur of the lemma. Hence gnýr uses {{is-ndecl|m,,ir.##.j}} (since it has a nominative plural in -ir and a j-infix) and sjór uses {{is-ndecl|m,s:ar,ir.##}} (since it has genitive singular in either -s or -ar and nominative plural in -ir).
• stem:... lets you set the stem arbitrarily. (# and ## here have the same meaning as when standing alone; hence # is equivalent to stem:# and ## is equivalent to stem:##.) A noun that uses this is Jesús (“Jesus”), with a highly irregular declension:

{{is-ndecl|m.stem:Jesú.acc-:m[archaic or Biblical].dat+gen-}}

which produces

Declension of Jesús (sg-only masculine)

indefinite singular
nominative	Jesús
accusative	Jesú, Jesúm1
dative	Jesú
genitive	Jesú

¹Archaic or Biblical.

Here, the stem is set to not include final -s and overrides are required for all remaining cases. Note that an alternative to setting the stem like this is decllemma:..., which says to decline the term entirely (except in the lemma form itself) as if the lemma were something else. This is used by e.g. maður (“man, human”), which sets the following:

{{is-ndecl|m,,^/^ir.decllemma:mannur}}

which produces

Declension of maður (masculine irreg-stem)

	singular		plural
	indefinite	definite	indefinite	definite
nominative	maður	maðurinn	menn	mennirnir
accusative	mann	manninn	menn	mennina
dative	manni	manninum	mönnum	mönnunum
genitive	manns	mannsins	manna	mannanna

Here, the lemma is declined as if it were mannur except in the nominative singular, and a nominative plural override supplies the irregular forms menn and mennir. (Other examples that use decllemma:... are mær (“maiden”), declined like mey, and feminine plurale tantum noun dyr (“door, doorway”), declined as if it were dyrir.)

There are additional indicators to control stems used in certain circumstances, such as in the plural or before a vowel. They are:

• vstem:... lets you override the stem used before vowels. alin (“ell (unit of measurement)”) uses this, since it has contraction plus irregular lengthening of the a before a vocalic ending:

{{is-ndecl|f.vstem:áln}}

which produces

Declension of alin (feminine)

	singular		plural
	indefinite	definite	indefinite	definite
nominative	alin	alinin	álnir	álnirnar
accusative	alin	alinina	álnir	álnirnar
dative	alin	alininni	álnum	álnunum
genitive	álnar	álnarinnar	álna	álnanna

• plstem:... lets you override the stem used in the plural. eyrir (1/100 of a krona) uses this, since it has an irregular plural aurar:

{{is-ndecl|m.plstem:aur}}

which produces

Declension of eyrir (masculine)

	singular		plural
	indefinite	definite	indefinite	definite
nominative	eyrir	eyririnn	aurar	aurarnir
accusative	eyri	eyrinn	aura	aurana
dative	eyri	eyrinum	aurum	aurunum
genitive	eyris	eyrisins	aura	auranna

• plvstem:... lets you override the stem specifically used before vowels in the plural. No terms currently use it but it is provided for completeness.

Miscellaneous boolean indicators

The following additional indicators can be specified in particular situations:

• adj: Term is an adjective. If this is specified, it should come first, and it changes the allowed indicators that can occur in the rest of the spec. See #Multiword terms for more information.
• indecl: Noun is indeclinable. Normally used in the headword, and no declension table is given. Can also be used to indicate mostly-indeclinable terms with overrides to indicate the declined forms.
• decl?: Unknown declension. Normally used in the headword, and no declension table is given.
• builtin: Requests a built-in declension for certain highly irregular words whose declensions are built into the module. Currently, all of these terms are pronouns: ég, þú, við, þið, hann, hún, það, þeir, þær, þau and sig.
• rstem: Specifies that a masculine or feminine term uses the r-stem declension pattern. Used specifically for the kinship terms faðir, móðir, bróðir, systir and dóttir.
• já: Specifies that a neuter term in -é uses the já-declension pattern, i.e. -já- appear instead of -é- in certain inflections.
• weak: Specifies that a masculine term in -andi should be declined as a normal weak noun instead of using the special present participle inflection pattern. Examples are andi (“breath”), landi (“populace; fellow countryman”); samlandi (“compatriot”); and fjandi (“devil”) (fjandi (“enemy”) does inflect using the present participle pattern).
• iending: For use with definite-only terms whose clitic starts with an i-; indicates that the lemma ends in an elided -i instead of a consonant. An example where this is needed is Bandaríkin (“the United States”), which is based on the term ríki and which would have an incorrect declension if iending is not used.
• linkasis: Prevents linking inflected words in multiword expressions to their computed lemma and instead links to the form as given. Useful e.g. for plurale tantum and definite-only nouns occurring in multiword expressions, as the default is to link to the synthesized singular indefinite form.
• ~: Link to the lowercase equivalent of the synthesized lemma. Used in multiword expressions; see #Multiword terms for more information.

Scraping declensions from elsewhere

To simplify specifying the declension of compounds of terms declined irregularly, a system of scraping the declension of another term is provided. Here, "scraping" means looking up the declension of a term found on another page and using it. For example, there are a large number of compounds of maður (“man”), which is notable irregular in its declension ({{is-ndecl|m,,^/^ir.decllemma:mannur}}). Rather than requiring that all of them repeat this declension (adjusted appropriately for the particular compound), the scraping system is provided to do this repetition and adjustment for you. The syntax of a term like aðalmaður (“member; leader”) looks like {{is-ndecl|@m}}. The @ sign requests scraping and the following letter or letters identify the suffix of the compound that should be scraped. In this case, the @m syntax means "find the last m in the word and use it and everything to its right as the lemma to scrape". (For this reason, all compounds of maður will use the same syntax.) This results in the following:

Declension of aðalmaður (masculine irreg-stem, based on maður)

	singular		plural
	indefinite	definite	indefinite	definite
nominative	aðalmaður	aðalmaðurinn	aðalmenn	aðalmennirnir
accusative	aðalmann	aðalmanninn	aðalmenn	aðalmennina
dative	aðalmanni	aðalmanninum	aðalmönnum	aðalmönnunum
genitive	aðalmanns	aðalmannsins	aðalmanna	aðalmannanna

Note how the title indicates the source lemma for the declension. (If you scrape a lemma that itself scrapes another lemma, this will work and creates a scraping chain. Such chains are only allowed to be 10 deep to avoid accidental infinite recursion.)

In some cases just indicating the first letter of the term to scrape won't work because the same letter is also found inside the term. To rectify this, supply more letters. For example, to scrape kirkja (“church”) in a lemma like aðalkirkja (“main part of a church”), use {{is-ndecl|@ki}}.

Scraping automatically adjusts any indicators that specify full words or parts of words that start from the beginning of the word by prepending the remaining part of the compound to them. For example, in the above example with maður, the decllemma:mannur indicator will be adjusted to decllemma:aðalmannur for use with aðalmaður. Other examples of indicators adjusted are stem overrides and full form overrides (those preceded with !).

The special syntax @@ does self-scraping, i.e. it attempts to scrape the declension of the term itself. This obviously won't work when specifying the declension of a single-word term (it will result in infinite recursion, which will abort with an error message), but it is frequently used in the headword, where {{is-noun}} or {{is-proper noun}} should normally use self-scraping to fetch the corresponding declension specified using {{is-ndecl}}. It is also frequently found in multiword terms to fetch the declension of individual terms in the expression. See below for more details.

If two calls to {{is-ndecl}} exist on the same page (even if they have identical declensions), the above scraping syntax won't work. To rectify this, it is necessary to give each declension an ID and specify the ID when scraping. Specifically, each call to {{is-ndecl}} should include a parameter |id=... giving a unique ID to the particular declension (preferably something short, obvious and memorable), and the scraping syntax should specify this ID after the scrape request itself, preceded by a colon. For example, the word skeið has to meanings, feminine "spoon" and neuter "span (of time)". The declension for the feminine word might write {{is-ndecl|f,,ar|id=spoon}} to give that declension the ID spoon, and matskeið (“tablespoon”) could then scrape its declension using {{is-ndecl|@s:spoon}}.

Sometimes it is desired to specify a different declension for use when scraping vs. for use in the term itself. An example is köttur (“cat”), which has archaic or literary accusative plural köttu in addition to normal ketti. It is simultaneously desirable to be able to include this alternative accusative plural form in the declension for köttur while not including it in any compounds derived from köttur. This is done by specifying the declension to use for lemmas that scrape this declension in the |deriv= parameter, as follows:

{{is-ndecl|m,ar,ir.unumut.imut.accpli:u[archaic or literary]|deriv=m,ar,ir.unumut.imut}}

which produces

Declension of köttur (masculine)

	singular		plural
	indefinite	definite	indefinite	definite
nominative	köttur	kötturinn	kettir	kettirnir
accusative	kött	köttinn	ketti, köttu1	kettina
dative	ketti	kettinum	köttum	köttunum
genitive	kattar	kattarins	katta	kattanna

¹Archaic or literary.

while a term like flækingsköttur (“stray cat”) that uses {{is-ndecl|@k}} to scrape the declension of köttur will yield

Declension of flækingsköttur (masculine, based on köttur)

	singular		plural
	indefinite	definite	indefinite	definite
nominative	flækingsköttur	flækingskötturinn	flækingskettir	flækingskettirnir
accusative	flækingskött	flækingsköttinn	flækingsketti	flækingskettina
dative	flækingsketti	flækingskettinum	flækingsköttum	flækingsköttunum
genitive	flækingskattar	flækingskattarins	flækingskatta	flækingskattanna

I.e. the archaic or literary ending is mentioned in the base noun köttur but not any derived nouns.

A couple other things to mention are scraping a capitalized base noun and scraping a suffix. For example, it is desirable for the given name Aðalbjörn to scrape the declension of Björn, but the latter is not a proper suffix of the former due to the capital letter. In this case, use {{is-ndecl|@B}} as the declension for Aðalbjörn and it will automatically scrape Björn and adjust the case of any stem, decllemma:... or full form overrides. A similar situation comes up when scraping a suffix. For example, to have the patronymic Einarsson scrape the suffix -son, use {{is-ndecl|@-s}}, and it will automatically scrape the declension of -son and make appropriate adjustments.

You are free to specify other indicators along with the scraping indicator. These override the properties taken from the scraped lemma. As an example, blástur (“the act of blowing; breeze, wind”) is declared as {{is-ndecl|m.#.imut}} (which means the stem is blástur-, contracting to blástr- before vowels, and i-mutation takes place before -i in the dative singular). This is a singular and plural term; but derived term aðblástur (“preaspiration”) is singular-only. Thus it specifies {{is-ndecl|@b.sg}}. In conjunction with this, it should be noted that a proper noun that scrapes a common noun will automatically be singular-only unless the scraped noun explicitly specifies both to indicate that is has a plural (this is done for example by -son so that patronymics that scrape it automatically get a plural). If this is not desired, it must be specified explicitly; e.g. demonyms such as Brasilíumaður (“Brazilian (person)”) must specify {{is-ndecl|@m.dem}} to simultaneously scrape maður and get treatment as a demonym (equivalent to a common noun). A couple of other examples are andfýla (“halitosis, bad breath”), which scrapes fýla (“stench, reek”), which is a plural; andfýla also has a plural per BÍN but it is very rare. To indicate this with a footnote, use {{is-ndecl|@f.addnote[.*_p][very rare]}}.

Footnotes

As shown in various examples above, you can attach footnotes to many of the indicators. Footnotes are specified in square brackets following a given indicator and should be written with an initial lowercase letter and without a final period/full stop, as in [rare] or [only in set phrases]. You can include multiple footnotes after a single indicator using multiple sets of square brackets, e.g. [rare][only in set phrases], although this is not common. Footnotes are automatically numbered in the order they are processed in the table (which generally processes left-to-right and then up-and-down), and duplicative footnotes are deduplicated, e.g. if multiple terms are identified as [rare], there will only be a single footnote found in the footnote section at the bottom of the table, with a single associated number. Footnotes at the bottom of the table are automatically converted into sentence form, i.e. the first word is capitalized and the whole footnote followed by a period/full stop (.). The same footnotes may also appear as qualifiers on inflections specified in the headword, and in that case they remain as-is (which is why it is important to give them lowercase and without any final period/full stop).

The following indicators take footnotes:

• All overrides, both those specified directly after the gender and separate, arbitrary form overrides.
• All control specs (mutation/infixing/contraction specs).
• Footnotes can also appear as an indicator by themselves; this applies the footnote to every form. (This is chiefly useful when alternant specs are present; see #Alternant specs below.)
• Finally, footnotes can be added to arbitrary forms using the addnote indicator, which takes the form addnote[SPEC][FOOTNOTE][FOOTNOTE].... Here, SPEC is either a single slot name, a Lua pattern matching multiple slot names (anchored on both ends), or a comma-separated list of either. The slot names here are of the form e.g. ind_dat_s for the indefinite dative singular and def_gen_p for the definite genitive plural. The most useful and common Lua patterns to use are .*_s, which matches all singular slots, and .*_p, which matches all plural slots. For example, the word kæla (“coolness”) is found in the plural, but rarely; this can be indicated using {{is-ndecl|f.addnote[.*_p][rare]}} to add a footnote [rare] to all plural slots.

Alternant specs

The alternant spec syntax lets you specify two or more different declensions for a given term. Some variations in declension can be handled by control specs (which allow multiple comma-separated values to be given) or by overrides, but not all variations can be handled this way. For example, akkur (“benefit, advantage”) can either be declined with stem akkur- (contracting to akkr- before vowels) or with stem akk-. Since only a single stem can be specified, there is no easy way to include both variants in a single table except for using an alternant spec. The syntax is as follows: {{is-ndecl|((SPEC1,SPEC2,...))}} i.e. comma-separated specs enclosed in double parentheses. Each spec can actually be a multiword expression (see #Multiword terms below) or a simple spec. In this case, the following suffices:

{{is-ndecl|((m.#.sg,m.sg.dati/i))}}

which produces

Declension of akkur (sg-only masculine)

	singular
	indefinite	definite
nominative	akkur	akkurinn
accusative	akkur, akk	akkurinn, akkinn
dative	akkri, akki	akkrinum, akkinum
genitive	akkurs, akks	akkursins, akksins

The first spec m.#.sg specifies a masculine, singular-only term whose stem includes the -ur ending (the # indicator). The second spec m.sg.dati/i is similar but omits the # indicator, which results in a stem akk- instead of akkur-. (In the second case, a dative override must be given; see the section #Default dative singular for masculine nouns above for why.)

Another example is hringur (“ring”), which has different plurals depending on meaning: plural in -ir with j-infixing in the plural for all kinds of non-jewelry rings, circles, etc., but plural in -ar without j-infixing for jewelry rings. To indicate this, use the following:

{{is-ndecl|((<m,,ir[usually for non-jewelry].j>,<m,,ar[usually for jewelry].dat->))}}

which produces

Declension of hringur (masculine)

	singular		plural
	indefinite	definite	indefinite	definite
nominative	hringur	hringurinn	hringir1, hringar2	hringirnir1, hringarnir2
accusative	hring	hringinn	hringi1, hringa2	hringina1, hringana2
dative	hring	hringnum	hringjum, hringum	hringjunum, hringunum
genitive	hrings	hringsins	hringja, hringa	hringjanna, hringanna

¹Usually for non-jewelry.
²Usually for jewelry.

Here, because the individual specs include commas in them, it is necessary to enclose the specs in angle brackets to avoid the commas embedded in the specs from being interpreted as top-level spec separators. (As a general rule you can always enclose an inflection spec in angle brackets and also include the lemma directly before the angle brackets; both are routinely done in multiword expressions, as described in the #Multiword terms section below.)

Finally, the following example for spónn (“chip; veneer; spoon”) shows the use of an alternant-level footnote (see #Footnotes above):

{{is-ndecl|((<m,s:ar[dated],ir.imut.dati>,<m.[proscribed].dati>))}}

which produces

Declension of spónn (masculine)

	singular		plural
	indefinite	definite	indefinite	definite
nominative	spónn	spónninn	spænir, spónar1	spænirnir, spónarnir1
accusative	spón	spóninn	spæni, spóna1	spænina, spónana1
dative	spæni, spóni1	spæninum, spóninum1	spónum	spónunum
genitive	spóns, spónar2	spónsins, spónarins2	spóna	spónanna

¹Proscribed.
²Dated.

The second alternant lacks i-mutation in the dative singular and nominative/accusative plural, and is proscribed. The footnote proscribed will appear on all forms that are different between the two alternants, but not on any that are the same. (This is the default for how deduplication of forms works when the forms to be deduplicated differ in their footnotes. This can be changed by adding a footnote modifier at the beginning of one of the footnotes, as follows: (a) if a footnote on the second form being deduplicated begins with ! or +, that footnote will be added to the footnotes, if any, of the first form rather than being discarded; (b) if a footnote on the first form being deduplicated begins with *, that footnote will be dropped if the second form has any footnotes, a sort of XOR behavior.)

Multiword terms

Multiword terms have their own syntax and considerations. The general syntax is to repeat the lemma, placing angle brackets after each lemma needing inflection and putting a standard inflection spec inside of angle brackets. For example, for bland í poka (“candy mix in a bag; (figurative) grab bag, assortment”), use:

{{is-ndecl|bland<n.sg> [[í]] [[poki|poka]]}}

which produces

Declension of bland í poka (sg-only neuter)

	singular
	indefinite	definite
nominative	bland í poka	blandið í poka
accusative	bland í poka	blandið í poka
dative	blandi í poka	blandinu í poka
genitive	blands í poka	blandsins í poka

Alternatively and preferably, use scraping to pick up the noun declensions automatically:

{{is-ndecl|bland<@@> [[í]] [[poki|poka]]}}

which results in the same inflections as above. Note that individual words that are not inflected should be formatted as links; this ensures that the corresponding call to {{is-noun}} will have the words correctly linked. In this case, that would result in:

bland í poka n (genitive singular blands í poka, no plural)

It is not usually necessary to link terms with associated angle-bracket inflections; that happens automatically.

An example with two inflected terms is afturbeygð sögn (“reflexive verb”), which should be specified as follows:

{{is-ndecl|afturbeygð<adj> sögn<@@>}}

which produces

Declension of afturbeygð sögn (feminine, based on sögn)

	singular		plural
	indefinite	definite	indefinite	definite
nominative	afturbeygð sögn	afturbeygða sögnin	afturbeygðar sagnir	afturbeygðu sagnirnar
accusative	afturbeygða sögn	afturbeygðu sögnina	afturbeygðar sagnir	afturbeygðu sagnirnar
dative	afturbeygðri sögn	afturbeygðu sögninni	afturbeygðum sögnum	afturbeygðu sögnunum
genitive	afturbeygðrar sagnar	afturbeygðu sagnarinnar	afturbeygðra sagna	afturbeygðu sagnanna

The adj indicator specifies that the first term is an adjective and should be inflected accordingly, and the @@ indicator on sögn automatically fetches the inflection of that word. The code is smart enough to propagate the feminine gender of sögn to the adjective and only use the feminine inflections of the adjective when constructing the combined inflection. It also knows that the lemma is afturbeygður (“reflexive”), and will appropriately link the term in the {{is-noun}} headword call, as follows:

afturbeygð sögn f (genitive singular afturbeygðrar sagnar, nominative plural afturbeygðar sagnir)

In most cases, masculine and feminine adjective forms (strong or weak), as well as weak neuter adjective forms, need only the adj indicator. Strong masculine adjective forms are used directly as the lemma while other adjective forms derive the lemma as follows:

1. Drop any weak ending to get the stem.
2. Then, if the ends in -nn or -ll, add -ur.
3. Else, if the stem ends in -in (if it's an adjective form), or any of -al/-ul/-il or -an/-in/-un (if it's a noun form) [excluding special cases like -ein and -aul], add -ur. The logic here is that doubling the last letter (as in the next step) would result in a term that contracts, which might result give incorrect results.
4. Else, if the stem ends in -n or -l preceded by a vowel, double the last consonant.
5. Else, if the stem ends in -n or -l (preceded by a consonant) or in -r or -s, leave it as-is.
6. Else, if the stem ends in a vowel, add -r.
7. Else, add -ur.

This correctly produces the lemma in most cases, but not all. Those remaining cases need additional help; see below.

All strong neuter adjective forms, as well as other forms where the above rules fail, need help to derive the correct lemma. Generally, this is done in one of two ways: (a) a slash substitution spec, which changes the last few letters of the form; or (b) a full lemma spec, which directly specifies the lemma. Slash substitution specs are more common and come in two varieties: one-part and two-part. An example of a one-part slash substitution spec is tvöfalt<adj/dur>, which says to remove the last letter from the neuter adjective form and add -dur in order to form the lemma tvöfaldur (“double”). This might be used in a term such as tvöfalt vaff (“double-u”, literally “double v”), which would use:

{{is-ndecl|tvöfalt<adj/dur> vaff<@@>}}

which produces

Declension of tvöfalt vaff (neuter, based on vaff)

	singular		plural
	indefinite	definite	indefinite	definite
nominative	tvöfalt vaff	tvöfalda vaffið	tvöföld vöff	tvöföldu vöffin
accusative	tvöfalt vaff	tvöfalda vaffið	tvöföld vöff	tvöföldu vöffin
dative	tvöföldu vaffi	tvöfalda vaffinu	tvöföldum vöffum	tvöföldu vöffunum
genitive	tvöfalds vaffs	tvöfalda vaffsins	tvöfaldra vaffa	tvöföldu vaffanna

The number of letters removed from the end in a one-part substitution spec depends on the gender, number and state of the adjective form, specifically:

1. Weak forms remove one letter.
2. Strong neuter singular forms remove one letter.
3. Strong feminine singular and neuter plural forms remove no letters.
4. Strong masculine and feminine plural forms remove two letters.

If this isn't sufficient, use a two-part substitution spec, as for ryðfrítt, the strong neuter singular form of ryðfrír (“stainless”, literally “rust-free”). This type of spec explicitly gives the letters to remove as well as their replacement, as follows:

{{is-ndecl|ryðfrítt<adj/tt/r.##> stál<@@.sg>}}

which produces

Declension of ryðfrítt stál (sg-only neuter, based on stál)

	singular
	indefinite	definite
nominative	ryðfrítt stál	ryðfría stálið
accusative	ryðfrítt stál	ryðfría stálið
dative	ryðfríu stáli	ryðfría stálinu
genitive	ryðfrís stáls	ryðfría stálsins

Here, we use a two-part slash substitution spec to replace -tt with -r, along with the stem control indicator ## (specifying that the stem of ryðfrír is ryðfrí- without the -r).

Finally, for highly irregular adjective forms, it may be easiest to specify the lemma outright. An example of this is tvö pör (“two pair (in poker)”), which uses the following:

{{is-ndecl|tvö<adj:tveir.builtin> pör<n.pl.indef>}}

which produces

Declension of tvö pör (pl-only neuter)

indefinite plural
nominative	tvö pör
accusative	tvö pör
dative	tveimur pörum, tveim pörum
genitive	tveggja para

Note the colon following the adj indicator; this is used to specify the lemma directly. Along with this, the builtin indicator is used to request the special built-in declension of tvö, which the adjective module Module:is-adjective knows how to inflect. For neuter plurals like pör, unumut is the default, so it correctly generates the genitive plural para and the lemma par in the associated call to {{is-noun}}, as can be seen by invoking it:

tvö pör n pl (plural only, genitive plural tveggja para)

If the adjective you are inflecting is a comparative, you need to specify this using the iscomp indicator; otherwise, it will wrongly be declined as a regular weak adjective. An example of this is eldri borgari (“senior citzen”):

{{is-ndecl|[[gamall|eldri]]<adj.iscomp> borgari<@@>}}

which produces

Declension of eldri borgari (masculine, based on borgari -> -ari)

	singular		plural
	indefinite	definite	indefinite	definite
nominative	eldri borgari	eldri borgarinn	eldri borgarar	eldri borgararnir
accusative	eldri borgara	eldri borgarann	eldri borgara	eldri borgarana
dative	eldri borgara	eldri borgaranum	eldri borgurum	eldri borgurunum
genitive	eldri borgara	eldri borgarans	eldri borgara	eldri borgaranna

This, incidentally, is one of the cases where it is necessary to explicitly link the adjective lemma. (The alternative would be to specify adj:gamall along with an explicit adjective comparative spec to map back to eldri, something like eldri<adj:gamall.comp:eldri.iscomp>, which is more work and in fact not even supported currently.) Some other examples where explicit linking of adjectives is needed:

• Superlatives, including but not limited to those that lack a positive form, such as hæstiréttur (“high court, supreme court”), which require a spec like {{is-ndecl|[[há|hæsti]]<adj>réttur<@@>}}; and efsta stig (“superlative degree”), which requires a spec like {{is-ndecl|[[efri|efsta]]<adj> stig<@@>}}. (The rules above would construct lemmas hæstur and efstur respectively, which are fine for declining the weak adjective forms, but insufficient for correct linking in the headword.)
• Weak adjectives in general, especially when the adjective is derived through a special, non-default process such as contraction or j-infixing, as with gamla settið (“one's parents (humorous)”, literally “the old set”), which could use {{is-ndecl|[[gamall|gamla]]<adj> settið<n.def.sg>}}; litlifingur (“little finger”), which could use {{is-ndecl|[[lítill|litli]]<adj>fingur<@@>}}; Nýja-Jórvík (“New York”), which could use {{is-ndecl|[[nýr|Nýja]]<adj>-Jórvík<@@>}}; and þriðja persóna, which could use {{is-ndecl|[[þriðji|þriðja]]<adj> persóna<@@.sg>}} (here the adjective is weak-only and the default rules would construct a strong adjective lemma þriðjur).

One more thing to note is the ~ indicator, which is used with a capitalized adjective or noun form and says to lowercase the term when linking. Examples of its use are in Írska lýðveldið (“the Irish Republic”), which would use {{is-ndecl|Írska<adj.~> lýðveldið<n.def.iending.proper>}} to ensure that Írska is linked to írskur (“Irish”) and not the capitalized equivalent, and Þriðja Ríkið (“the Third Reich”), which would use {{is-ndecl|[[þriðji|Þriðja]]<adj> Ríkið<n.sg.def.iending.~>}} to ensure that Ríkið links to ríki (“kingdom, realm, empire, sovereign state”).