2. Monosyllables characterised by oi drop i and add a; as, feoil f. flesh, g. s. feola; tòin f. bottom, g. s. tòna; sròin f. the nose, g. s. sròine or sròna.
3. Monosyllables characterised by ui change ui into a or o, and add a; as, muir f. the sea, g. s. mara; fuil f. blood, g. s. fola or fala; druim f. a ridge, g. s. droma. Except sùil f. the eye, g. s. sùla; cuid f. a part, g. s. codach or cuid.
4. A few feminine polysyllables in eir form their genitive like monosyllables; as, inneir f. dung, g. s. inneire; suipeir f. supper, g. s. suipeire.
5. The following dissyllables seem to have formed their genitive like monosyllables, and then suffered a contraction. Sometimes the characteristic vowel is retained, and sometimes it is thrown away, the final e of the genitive being converted into a, when requisite to suit an antecedent broad vowel.
| Amhainn, f. a river, | g. s. aimhne, contracted for | amhainne |
| Aghainn, Aghann f. a pan, | g. s. aighne, | aghainne |
| Banais f. a wedding, | g. s. bainse, | banaise |
| Coluinn f. the body, | g. s. colna, colla | coluinne |
| Duthaich f. a country, | g. s. duthcha, | duthaiche |
| Fiacail f. a tooth, | g. s. fiacla, | fiacaile |
| Gamhuinn m. a steer, | g. s. gamhna, | gamhuinne |
| Gualainn f. the shoulder, | g. s. guaille, | gualainne |
| Madainn f. morning, | g. s. maidne, | madainne |
| Obair f. work, | g. s. oibre, | obaire |
| Uilinn f. the elbow, | g. s. uillne, | uilinne |
6. The following nouns form their genitive by dropping the characteristic small vowel; athair m. a father, g. s. athar; mathair f. a mother, g. s. mathar; brathair m. a brother, g. s. brathar; namhaid m. an enemy, g. s. namhad. Cnaimh m. a bone, g. s. cnamha; uaimh f. a cave, g. s. uamha. Mil f. honey, has g. s. meala.
7. A few monosyllables ending in a vowel have their genitive like the nominative; as, ni m. a thing, ti m. a person, ré m. the moon; to which add righ m. a king.
Dative. The dative singular is like the nominative; as, duine m. a man, d. s. duine; madainn f. morning, d. s. madainn.
Vocative. The vocative singular is like the nominative, as, caraid m. friend, v. s. charaid; mathair f. mother, v. s. mhathair.