adeirrig

Old Irish

The prefixes are either aith- +‎ ar- or aith- +‎ ess-. The root was formerly believed to be Proto-Celtic *regeti, from Proto-Indo-European *h₃reǵ-. Nowadays however an unrelated verb *reketi is instead reconstructed as the root of ad·eirrig,^[1] in consideration of Brythonic relatives like Cornish edrek (“regret”).^[2]

ad·eirrig (prototonic ·aithirrig, verbal noun aithirge or aitherrach)

For quotations using this term, see Citations:adeirrig.

Complex, class B I present, t preterite, s future, s subjunctive

		1st sg.	3rd sg.	2nd pl.	3rd pl.	Passive sg.	Passive pl.
Present indicative	Deut.		ad·errig, ad·eirrig; atann·eirrig (with infixed pronoun dan-)
Present indicative	Prot.

Imperfect indicative	Deut.
Imperfect indicative	Prot.

Preterite	Deut.
Preterite	Prot.		·atherracht, ·aitherracht

Perfect	Deut.
Perfect	Prot.

Future	Deut.	ad·errius					ad·ersetar
Future	Prot.		·aithir	·aithirsid	·aithirset	·aithirrestar

Conditional	Deut.
Conditional	Prot.

Present subjunctive	Deut.	ad·errius					ad·ersetar
Present subjunctive	Prot.		·aithir	·aithirsid	·aithirset	·aithirrestar

Past subjunctive	Deut.
Past subjunctive	Prot.

Imperative				aithirgid

Verbal noun		aithirge, aitherrach
Past participle
Verbal of necessity

Note: The present and past subjunctive are identical to the future and conditional, respectively.

Middle Irish: aithrigid
- Irish: athraigh
- Manx: arree
- Scottish Gaelic: atharraich

Mutation of *adeirrig*
radical	lenition	nasalization
ad·eirrig (pronounced with /h/ in h-prothesis environments)	unchanged	ad·n-eirrig

Note: Certain mutated forms of some words can never occur in Old Irish.
All possible mutated forms are displayed for convenience.

^ Matasović, Ranko (2009) “*rek-o”, in Etymological Dictionary of Proto-Celtic (Leiden Indo-European Etymological Dictionary Series; 9), Leiden: Brill, →ISBN, page 308
^ Gordon, Randall Clark (2012) “-rech-”, in Derivational Morphology of the Early Irish Verbal Noun, Los Angeles: University of California, §3.1.96, page 276