Appendix:Irish nouns

Irish has five noun declensions, each with four cases (nominative, vocative, genitive, dative), and singular and plural forms. Noun endings are typified by broad and slender consonants, and vowels; case endings are characterised by the broadening and slenderising of consonants, and the addition of suffixes.

The defining feature of each declension is the genitive singular. The dative singular has distinctive features in some declensions.

Plurals are categorised as weak if the genitive plural is the same as the nominative singular; and strong if the genitive plural is the same as the nominative plural. Weak plurals are formed by slenderising consonants, or adding the suffix &#8209;a. Strong plural suffixes include &#8209;aí, &#8209;anna, &#8209;ta and &#8209;acha, and a few nouns in -a/e with syncopation. The dative plural &#8209;aibh is non-standard, and considered archaic/dialectical.

The vocative has the same form as the nominative in the second to fifth declensions. In the first declension, it is slender in the singular and broad + a in the plural.

There are two genders in Irish, masculine and feminine. The gender of nouns in each declension is somewhat mixed, but there are clear patterns.

Irish nouns undergo initial mutations.

The definite article
The entry for the definite article has a comprehensive declension table, including initial mutation rules.

As an example of the evolution of the article from Proto-Celtic, that of the nominative singular masculine, with t-prothesis before a vowel, can be given as: > *(s)ind >  >  t-.

The demonstrative retains the Proto-Celtic initial 's'. The 's' also appears in the Modern Irish contractions of with the article: , (n), , as well as the dialectical , ,.

There is no indefinite article in Irish.

Irregular nouns
The defining feature of each declension is the genitive singular. By this definition, a few nouns defy classification, notably:
 * , gs mná
 * deirfiúr, deirféar
 * , Dé
 * , lae
 * leaba, leapa
 * , míosa
 * siúr, siúrach

The Caighdeán lists deoch and teach as irregular, but just a little digging shows them to be second declension nouns.
 * deoch &rarr; gs. digh + e > dí
 * &rarr; gs. tigh + e > tí

Multiple declension nouns
Some Irish nouns belong to more than one declension. There is a distinction to be made between historical/dialectical declension variants of a particular noun, and homonyms. A good example of the latter is from Old Irish, and  from Old Irish nes.

The following is not meant as an exhaustive list.

Wiktionary templates
Irregular:

For declension-specific templates, see the source list on About Irish, or under the relevant appendices.

Categories

 * Category:Irish appendices


 * Category:Irish first-declension nouns
 * Category:Irish second-declension nouns
 * Category:Irish third-declension nouns
 * Category:Irish fourth-declension nouns
 * Category:Irish fifth-declension nouns

Appendices

 * Appendix:Irish first-declension nouns
 * Appendix:Irish second-declension nouns
 * Appendix:Irish third-declension nouns
 * Appendix:Irish fourth-declension nouns
 * Appendix:Irish fifth-declension nouns