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Defence in Irish (Cosaint): Meaning, Pronunciation, Usage

‘cosaint’ also means: defence (legal) · defence (sport) · cost

The Irish for defence is cosaint, a feminine noun (plural cosaintí). Ag cosaint is defending, from the verb cosain.
Updated October 2026Report a mistake

How to say “defence” in Irish

Irish:
cosaint
English:
defence, defence (legal), defence (sport), cost
Word type:
noun (verbal noun)
Verbal noun of:
cosain, to defend (ag cosaint, defending)
Gender:
feminine, third declension
Pronunciation:
“KUS-int”  /ˈkɔsˠənʲtʲ/
Various forms
Plural:
cosaintí (defences)
Genitive singular:
cosanta, na cosanta (e.g. Aire Cosanta, Minister for Defence)
Genitive plural:
cosaintí, na gcosaintí (e.g. láidreacht na gcosaintí, the strength of the defences)

What does “cosaint” mean?

“Cosaint” has four alternative meanings. The most common comes first.

defence
The act of defending or protecting someone or something against attack or harm; verbal noun of the verb cosain.Also: defense, protection, defending, protecting.
3 other meanings: defence (legal) or defence (sport) or cost
2defence (legal)
The case made on behalf of an accused person in court, or the side defending them.Also: defence, legal defence, the defence.
3defence (sport)
The players or tactics in a team game whose job is to stop the other side scoring.Also: defence, defending, back line.
4cost
What something costs, as in the price paid to keep or defend it; also the verbal noun of cosain meaning to cost.Also: costing.

“Cosaint” as a verbal noun

After ag, cosaint means defending: it is the verbal noun of the verb cosain (to defend). A noun that follows it goes into the genitive.

agat
+
cosaintverbal noun
=
ag cosaintdefending

“Cosaint” with the article

The plural of defence in Irish is cosaintí. Here is cosaint after the article (an t-alt), in the singular and the plural.

an chosaint
the defence
Lenition: c becomes ch after an (feminine noun)
na cosaintí
the defences
Plural: no change after na

“Cosaint” in a sentence: Irish examples

Common Irish sentences using cosaint, the Irish word for defence.

Tá cosaint de dhíth ar na páistí.
The children need protection.
Bhí an chosaint go maith sa dara leath.
The defence was good in the second half.
D'oibrigh sí sa Roinn Cosanta ar feadh blianta.
She worked in the Department of Defence for years.
Labhair dlíodóir na cosanta leis an ngiúiré.
The defence lawyer spoke to the jury.
Thóg siad cosaintí láidre timpeall an bhaile.
They built strong defences around the town.
Sheas sé suas i mo chosaint.
He stood up in my defence.
Imríonn sé sa chosaint don chontae.
He plays in defence for the county.

Other nouns in Irish

More everyday Irish nouns to learn next.

Defence in Irish: frequently asked questions

What is the Irish for defence?

The Irish for defence is cosaint (pronounced “KUS-int”). It’s a feminine noun and the plural is cosaintí. Depending on context it can also mean defence (legal) or defence (sport) or cost.

How do you pronounce cosaint in Irish?

Cosaint is said like “KUS-int” (IPA /ˈkɔsˠənʲtʲ/).

What is the plural of defence in Irish?

The plural of cosaint is cosaintí; with the article, na cosaintí means “the defences”. The genitive plural is cosaintí, as in láidreacht na gcosaintí (the strength of the defences).

Does cosaint have more than one meaning?

Yes. Cosaint can mean defence, defence (legal), defence (sport) or cost, depending on context; the first is the most common.

Why does cosaint change to chosaint or gcosaint?

Irish changes the start of some words after certain words. After mo (my) cosaint becomes mo chosaint (lenition), and after ár (our) or i (in) it becomes ár gcosaint (eclipsis).

How do I say 'in defence of' something?

Use the preposition i with the possessive: i do chosaint 'in your defence', or ar son with the genitive in some contexts.

Is cosaint linked to the word for 'cost'?

Yes, the verb cosain means both 'defend' and 'cost', so cosaint can relate to either, though 'defence, protection' is by far the commonest sense.

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