-aí

See also: Appendix:Variations of "ai"

Irish

Pronunciation

IPA^(key): /iː/

Etymology 1

From earlier -aidhe, originally the Old Irish accusative and vocative plural ending of d-stem nouns. For example Old Irish arae, plural arada.

Alternative forms

-aidhe (obsolete)
-í (slender form)
-idhe (obsolete slender form)

Suffix

-aí

Ending of the plural of certain nouns.
‎beannacht (“blessing, greeting”) + ‎-aí → ‎beannachtaí

‎gnólacht (“commercial firm”) + ‎-aí → ‎gnólachtaí

Etymology 2

A merger of two different Old Irish suffixes. One the one hand, from Old Irish -id, from Proto-Celtic *-yatis, an extended variant of Proto-Celtic *-atis. On the other hand, from Old Irish -aige, from Proto-Celtic *sagyos (“seeker”).^[1]

Alternative forms

-aidhe, -oidhe, -uidhe (obsolete)
-í (slender form)
-idhe (obsolete slender form)

Suffix

-aí m

-er (person or thing that does an action indicated by the root verb)
‎feighil (“to watch, tend”) + ‎-aí → ‎feighlí (“watcher, tender”)
-ist (one who follows a particular ideology; member of a profession or one interested in something; person who uses something)
‎Búda (“Buddha”) + ‎-aí → ‎Búdaí (“Buddhist”)

‎eol (“knowledge”) + ‎-aí → ‎eolaí (“scientist, -ologist”)

‎roth (“wheel”) + ‎-aí → ‎rothaí (“cyclist”)
-ee (person to whom or a thing to which an action is done; person who or a thing that does an action; person who is the other party to a contract)
‎fostaigh (“employ”) + ‎-aí → ‎fostaí (“employee”)

‎neamhláithreach (“absent”) + ‎-aí → ‎neamhláithrí (“absentee”)

‎morgáiste (“mortgage”) + ‎-aí → ‎morgáistí (“mortgagee”)

Declension

Declension of -aí (fourth declension)

bare forms
	singular	plural
nominative	-aí	-aithe
vocative	a -aí	a -aithe
genitive	-aí	-aithe
dative	-aí	-aithe

forms with the definite article
	singular	plural
nominative	an -aí	na -aithe
genitive	an -aí	na -aithe
dative	leis an -aí don -aí	leis na -aithe

Derived terms

Irish terms suffixed with -aí (agent)

Etymology 3

From Old Irish -ide, variant form of -de used after a syncopated vowel.

Alternative forms

-aidhe, -idhe (superseded)
-í (slender form)

Suffix

-aí

Added to nouns to form adjectives.

Derived terms

Etymology 4

Alternative forms

-í (slender form)

Suffix

-aí m

Suffix used to form verbal nouns
‎tosaigh + ‎-aí → ‎tosaí

‎fiafraigh + ‎-aí → ‎fiafraí

References

^ Kim McCone (1994), chapter II, in K. McCone, D. McManus, C. Ó Háinle, N. Williams, L. Breatnach, editors, Stair na Gaeilge: in ómós do P[h]ádraig Ó Fiannachta (in Irish), Maynooth: Roinn na Sean-Ghaeilge, Coláiste Phádraig, →ISBN, section 21.3, page 172

[1] Kim McCone (1994), chapter II, in K. McCone, D. McManus, C. Ó Háinle, N. Williams, L. Breatnach, editors, Stair na Gaeilge: in ómós do P[h]ádraig Ó Fiannachta (in Irish), Maynooth: Roinn na Sean-Ghaeilge, Coláiste Phádraig, →ISBN, section 21.3, page 172

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