-իւն

From the Proto-Indo-European *-yōn- suffix. Compare Latin regiō, genitive regiōnis. Perhaps partly contaminated with Proto-Indo-European *-mno- adverbial formations, as shown by the parallels գոչիւն (gočʻiwn) / գոչումն (gočʻumn), լալիւն (laliwn) / լալումն (lalumn).

-իւն • (-iwn)

1. forming nouns related to the notion of sound, noise, and often having onomatopoeic origin

   գոչիւն ― gočʻiwn ― clamour, cry

   թնդիւն ― tʻndiwn ― sound, noise

   շառաչիւն ― šaṙačʻiwn ― clang, clatter

2. found in few other words, of opaque function (the etymology may be different)

   արիւն ― ariwn ― blood

   անկիւն ― ankiwn ― angle

   աւիւն ― awiwn ― fury

   աճիւն ― ačiwn ― ashes

   արդիւն ― ardiwn ― production

   հերիւն ― heriwn ― bodkin; awl, pricker

Nouns formed with this suffix (in the first sense) are indeclinable.

• Armenian: -յուն (-yun)

• J̌ahukyan, Geworg (1998) “-իւն”, in Hin hayereni verǰacancʻneri cagumə [The Origin of Old Armenian Suffixes] (Hayocʻ lezvi hamematakan kʻerakanutʻyan harcʻer; 2) (in Armenian), Yerevan: Anania Širakacʻi, pages 5–48