These exceptions apply to most rules for the aspiration of nouns as well as adjectives.
(d) The genitive of nouns of the 3rd and 5th declesions ought not to have the initial of the adjective following them aspirated. Usage, however, differs somewhat on this point.
(e) In the spoken language of Connaught the adjective is not aspirated in the dative singular masculine.
Rules for Eclipsing the Adjective.
151. (a) The adjective is usually eclipsed in the genitive plural, even though the article is not used before the noun; and if the adjective begins with a vowel n is prefixed.
(b) The initial of an adjective following a noun in the dative sing. should, as a rule, be aspirated; but whenever the noun is eclipsed after the article the adjective is often eclipsed also; aspiration in this case is just as correct as eclipsis, and is more usual.
Examples
152. Noun, Adjective and Article declined in combination.
| SINGULAR. | PLURAL. | |
| an fear mór, the big man. | ||
| Nom. & Acc. | an fear mór | na fir ṁóra |
| Gen. | an ḟir ṁóir | na ḃfear mór |
| Dat. | leis an ḃfear ṁór | leis na fearaiḃ móra |
| Voc. | a ḟir ṁóir | a ḟeara móra |
