Irish declension


The declension of Irish nouns, the definite article, and the adjectives is discussed on this page.

Nouns

Gender

Nouns in Irish are divided into two genders, masculine and feminine; the Old Irish neuter gender no longer exists. While gender should be learned when the specific noun is learned, there are some guidelines that can be followed:
Generally, nouns in singular form ending with broad consonants are masculine, while those ending in a slender consonant are feminine.
There are some exceptions, mostly dealing with specific endings and suffixes; for example, words ending in -óir/-eoir and -ín are categorically masculine, while words ending in -óg/-eog are feminine. This leads to some unexpected gender assignments, such as gasóg "boy scout" being feminine, and cailín "girl" masculine.

Case

Irish has four cases: common, vocative, genitive, and the dative or prepositional case.

Nominative

The nominative is used in the following functions:
  1. Sentence subject
  2. :Tá an cat ag ól. "The cat is drinking."
  3. Sentence object
  4. :Bhris Seán an fhuinneog. "Seán broke the window."
  5. Predicate of the copula
  6. :Is amadán é. "He is an idiot."
  7. Object of the prepositions gan "without", go dtí " to" and mar "like, as".
  8. :gan an t-airgead "without the money"
  9. :go dtí an t-am " to the time"
  10. :mar an chearc "like the hen"

    Vocative

The vocative is used in direct address, and is always preceded by the particle a, which triggers lenition. The first declension is the only declension in which the vocative is otherwise distinct from the nominative.
The genitive indicates possession and material of composition:
The object of a verbal noun also requires the genitive:
The object of a compound preposition is in the genitive. Formally, these prepositions are actually prepositional phrases.
The dative/prepositional is used as the object of most simple prepositions except gan and go dtí. In standard language, the dative is almost always identical to the nominative. Some dialects, however, have distinct standalone datives in the second and fifth declensions. In the standard language, only two words Éire and fiche have distinct datives - Éirinn and fichid, respectively. They are also found in certain fixed phrases with nouns of the second declension, such as os cionn.
There are five recognized declensions in Irish. The makeup of the declensions depends on three factors:
  1. the gender of the noun
  2. the formation of the genitive singular
  3. relation of genitive singular to nominative plural
The following chart describes the characteristics of each declension class:

First

The first declension is made up of masculine nouns. The nominative singular ends in a broad consonant, which is made slender in the genitive singular. The most common formation of the plural has the opposite pattern: the nominative ends in a slender consonant, the genitive in a broad consonant. The dative is identical to the nominative in both numbers, although an obsolete dative plural in -aibh is still sometimes encountered in old-fashioned literary style.
bád "boat"SingularPlural
Nominativebád báid
Vocativea bháid a bháda
Genitivebáid bád
Dativebád báid

When in the gen. sing. and nom. pl. of a polysyllabic word is made slender, it also becomes voiced, thus:
marcach "a horseman"SingularPlural
Nominativemarcach marcaigh ~
~
Vocativea mharcaigh ~
~ 		a mharcacha
Genitivemarcaigh ~
~ 		marcach
Dativemarcach marcaigh

Some nouns undergo a vowel change before the slender consonant of the genitive singular/nominative plural:
Many words of this declension form the plural with one of the endings -í, -ta, -tha, -anna. These are known as "strong plural" endings, which means the plural is identical in all cases in the standard language. Some examples:
Some nouns have a weak plural in -a:
Other strong plural formations are found in:
The second declension is made up of mostly feminine nouns, and features a nominative singular form that can end in either a broad or a slender consonant. The genitive singular ends in a slender consonant followed by -e. The most common plural form has a broad consonant followed by -a in the nominative, and a broad consonant alone in the genitive. The vocative has the same endings as the nominative, as does the dative in standard language.
bróg "shoe"SingularPlural
Nominativebróg bróga
Vocativea bhróg a bhróga
Genitivebróige bróg
Dativebróg
 		bróga
 

In Connacht Irish and Waterford Irish it is often the case that all nouns of the second declension in the nom. sg. end with a slender consonant.
In some Munster varieties as well as the old literary language, the dative singular is distinct and ends in a slender consonant alone, e.g. i mo bhróig "in my shoe".
When in the gen. sing. is made slender, it is also voiced, so > >. becomes, and is written -í.
girseach "little girl"SingularPlural
Nominative/Std. dativegirseach girseacha
Vocativea ghirseach a ghirseacha
Genitivegirsí girseach
Nonstandard Dativegirsigh girseachaibh

Many words in this declension form a strong plural with one of the endings -ta,-te, -acha or -eanna:
Other strong plural formations are found in:
The third declension is made up of masculine and feminine nouns. It is characterized by the genitive singular in -a. The majority of nouns in this class form the plural in -í. The final consonant of the stem may be broad or slender: it retains its quality in the plural, but is always broad in the genitive singular.
SingularPlural
Nominative/Vocative/Dativebroad or slender cons.-í
Genitivebroad cons. + -a-í

rás "race"SingularPlural
Nominative/Dativerás rásaí
Vocativea rás a rásaí
Genitiverása rásaí

Feminine nouns in -áint and -úint lose their t in the gen. sg.; those in -irt have -th- instead of -t- in the gen. sg.
Many words in this declension form the plural with one of the endings -anna or -acha:
Some words in Munster Irish also have a separate dative form:
The fourth declension is made up of masculine and feminine nouns. It is characterized by a genitive singular that is identical in form to the nominative/vocative/dative singular. The singular may end in a vowel or a consonant. The most common plural ending is -í.
SingularPlural
All casesVowel or consonant -í

comhairle " advice"SingularPlural
Nominative/Genitive/Dativecomhairle comhairlí
Vocativea chomhairle a chomhairlí

Many words of this declension form the plural with the following endings -tha/-te, -nna or -cha:
Other strong plural formations are found in:
One noun in this class has a weak plural:
The fifth declension is made up mostly of feminine nouns and is characterized by a genitive singular that ends in a broad consonant that has been added to the nominative/vocative/dative singular. The most common plural is strong, formed by adding -a to the genitive singular.
SingularPlural
Nominative/Vocative/DativeVowel or slender consonantGen. sg. + -a
Genitivebroad consonantGen. sg. + -a

cathair "city"SingularPlural
Nominative/Dativecathair cathracha
Vocativea chathair a chathracha
Genitivecathrach cathracha

In some Munster Irish varieties as well as the old literary language, the dative singular is distinct and ends in a slender consonant, for example, do phearsain "to a person", ón gcathraigh "from the city". In Éire, Éireann "Ireland" the dative Éirinn is still used in the standard language.
Some words form the genitive singular by changing the final consonant of the nominative singular to broad. The plural is then strong -eacha.
Other strong plural formations are found in:
Some nouns have weak plurals; here the genitive singular and genitive plural have the same form:
The most productive verbal nouns end with -adh or -ú. These originally belonged to the third declension, but synchronically are best regarded as separate declensions.
The 1st conjugation verbal noun in -adh has a genitive singular in -te/-ta and a plural in -tí.
The 2nd conjugation verbal noun in -ú has a genitive singular in -ithe and a plural in -ithe. These endings are pronounced the same regardless of the spelling distinction.
The following nouns are declined irregularly:
The definite article has two forms in Irish: an and na. Their distribution depends on number, case, and gender, and they trigger mutation partly on the basis of the initial sound of the following word. Each entry of the table gives an example of one noun starting with a consonant and one with a vowel.
Dative is used with all prepositions in Ulster usage; in Munster and the standard language it is used only with den "from the", don "to the", and sa "in the" but there are also Munster dialects in which only sa triggers lenition and den and don eclipse, as with every other article-preposition compound. In Connacht sa eclipses whereas den and don lenite. Dative is used outside Ulster with other prepositions.
The article never mutates a following d or t in the singular, and s is lenited to ts rather than the usual sh. s furthermore lenites in both dative and in the singular with feminine nouns but does not lenite at all with masculine nouns.
It does, however, eclipse t and d in Munster dialects and forms like "ag an ndoras" instead of the usual pattern "ag an doras", which is used in all other dialects, do occur.
There is no indefinite article in Irish, so depending on context cat can mean "cat" or "a cat".

Adjectives

Almost all adjectives in Irish can be used either predicatively or attributively. A predicative adjective is one that forms a part of the predicate, like red in the sentence The car is red. An attributive adjective directly modifies a noun, as in the red car.
A predicate adjective in Irish does not inflect:
A predicate adjective expressing a value judgment is often preceded by the particle go. This particle attaches a h to a following vowel.
In Ulster, go is not generally used in these cases.
An attributive adjective mostly follows the noun and is inflected:
There are four classes of declension of adjectives in Irish, which correspond to the first four declensions of nouns:
Nom. sg. ends with:Gen. sg. masc. ends with:Gen. sg. fem. ends with:
1st decl.broad cons.slender consonantslender consonant + -e
2nd decl.slender cons.slender consonantslender consonant + -e
3rd decl.slender cons. slender consonantbroad consonant + -a
4th decl.vowel= nom. sg.= nom. sg.

First declension

bacach "lame"Masc. sg.Fem. sg.Plural
Nominativebacachbhacachbacacha
Genitivebhacaighbacaíbacach

Second declension

Third declension

cóir "just"Masc. Sg.Fem. Sg.Plural
Nominativecóirchóircóra
Genitivechóircóracóir, córa

Fourth declension

This declension does not inflect, but it does mutate.
crua "hard"Masc. sg.Fem. sg.Plural
Nominativecruachruacrua
Genitivechruacruacrua

Irregular adjectives

;Notes
Irish adjectives have a comparative form equivalent to the comparative and superlative in English. The comparative does not undergo inflexion and is the same as the feminine singular genitive in regular and many irregular adjectives.

Regular formation

Irregular forms

Syntax of comparison

There are two constructions to express the comparative:
1) Copula + comparative form + subject + ná + predicate. The preterite of the copula causes lenition, while the present tense does not.
2) níos/ní ba/ní b’ + comparative + ná + predicate. Níos is used if the sentence is in the present or future tense.
Ní ba/ní b’, which triggers lenition, is used if the sentence is in the past tense. Ní b’ is used before words starting with vowels and ní ba before those starting with consonants.
A superlative is expressed as a relative clause: noun + is/ba/ab + comparative form.