noídiu

Old Irish

From Proto-Celtic *nowēdwūs (“unknowing”), from *ne + Proto-Indo-European *weyd- (“to see, know”). See also fíadu (from Proto-Celtic *weidwūs) for a related formation. The n-stem inflection is secondary; it is analogical to other n-stems that would also end in -ū in the nominative singular.

noídiu f (genitive noíden, nominative plural noídin)

Feminine n-stem
	Singular	Dual	Plural
Nominative	noídiu	noídin^L	noídin
Vocative	noídiu	noídin^L	noídena^H
Accusative	noídin^N	noídin^L	noídena^H
Genitive	noíden	noíden^L	noíden^N
Dative	noídin^L, noídiu^L	noídenaib	noídenaib
Initial mutations of a following adjective: ^H = triggers aspiration ^L = triggers lenition ^N = triggers nasalization

Old Irish mutation
Radical	Lenition	Nasalization
noídiu also nnoídiu after a proclitic ending in a vowel	noídiu pronounced with /n(ʲ)-/	unchanged
Note: Some of these forms may be hypothetical. Not every possible mutated form of every word actually occurs.