doaisféna

Old Irish

Prefixed with to- +‎ ess-. Related to as·féna (“to swear, testify, attest to”). Their base ·féna is from Proto-Celtic *wetnati, from Proto-Indo-European *weth₂- (“to say”).^[1]

do·aisféna (prototonic ·taisféna, verbal noun taisbénad)

to show, exhibit
- c. 800, Würzburg Glosses on the Pauline Epistles, published in Thesaurus Palaeohibernicus (reprinted 1987, Dublin Institute for Advanced Studies), edited and with translations by Whitley Stokes and John Strachan, vol. I, pp. 499–712, Wb. 18^d7
  .i. narraui eis .i. do·airfenus doib dús imbed comrorcon and et ni robe.
  narravi eis, i.e. I reported it to them to see if by chance there might be error within, and there wasn't any.

Complex, class A I present, s preterite, a subjunctive
		1st sg	3rd sg	passive sg
present indicative	deut.
present indicative	prot.			·taisfentar

imperfect indicative	deut.
imperfect indicative	prot.

preterite	deut.
preterite	prot.

perfect	deut.	do·airfenus	dos·airfen (with infixed pronoun s-)
perfect	prot.		·tarfen

future	deut.
future	prot.

conditional	deut.
conditional	prot.

present subjunctive	deut.		do·aisbena; do·airfena (ro-form)
present subjunctive	prot.		·taisfena

past subjunctive	deut.
past subjunctive	prot.

imperative				taisfentar

verbal noun		taisbénad
past participle
verbal of necessity

Middle Irish: taisbénaid, taispénaid
- Irish: taispeáin
- Scottish Gaelic: taisbean
- Manx: taishbyn

Mutation of *doaisféna*
radical	lenition	nasalization
do·aisféna (pronounced with /h/ in h-prothesis environments)	unchanged	do·n-aisféna

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

^ Matasović, Ranko (2009) “*wet-o-”, in Etymological Dictionary of Proto-Celtic (Leiden Indo-European Etymological Dictionary Series; 9), Leiden: Brill, →ISBN, page 418