accuis

Old Irish

Borrowed from Late Latin *accāsiō, from Latin occāsiō, whence also Middle Welsh achaws (modern Welsh achos).

accuis f

Feminine n-stem
	Singular	Dual	Plural
Nominative	accuis	aicsin^L	aicsin
Vocative	accuis	aicsin^L	aicsena^H
Accusative	aicsin^N	aicsin^L	aicsena^H
Genitive	aicsen	aicsen^L	aicsen^N
Dative	aicsin^L, accuis^L	aicsenaib	aicsenaib
Initial mutations of a following adjective: ^H = triggers aspiration ^L = triggers lenition ^N = triggers nasalization

From ad- + Proto-Celtic *kassis (“hatred”).[1]

accuis f (nominative plural acsi)

Feminine i-stem
	Singular	Dual	Plural
Nominative	accuis	accuis^L	aicsi^H
Vocative	accuis	accuis^L	aicsi^H
Accusative	accuis^N	accuis^L	aicsi^H
Genitive	aicseo^H, aicsea^H	aicseo^H, aicsea^H	aicse^N
Dative	accuis^L	aicsib	aicsib
Initial mutations of a following adjective: ^H = triggers aspiration ^L = triggers lenition ^N = triggers nasalization

Middle Irish: accais, acaiss, acuis (“cause; offense; hatred; venom”)
- Irish: aicis, acais (“venom, spite”)

Old Irish mutation
Radical	Lenition	Nasalization
accuis	unchanged	n-accuis
Note: Some of these forms may be hypothetical. Not every possible mutated form of every word actually occurs.

Griffith, Aaron (February 26, 2022), “On the old Irish third palatalisation and the 3sg. present of the copula”, in Ériu‎, volume 66, issue 1, →DOI, →ISSN, retrieved June 22, 2022, pages 39–62