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Castle in Irish (Caisleán): Meaning, Pronunciation, Usage

‘caisleán’ also means: mansion · cumulus cloud

The Irish for castle is caisleán, a masculine noun (plural caisleáin).
Updated October 2026Report a mistake

How to say “castle” in Irish

Irish:
caisleán
English:
castle, mansion, cumulus cloud
Word type:
noun
Gender:
masculine, first declension
Pronunciation:
“KASH-lawn”  /ˈkaʃlʲaːnˠ/
Various forms
Plural:
caisleáin (castles)
Genitive singular:
caisleáin, an chaisleáin (e.g. ballaí an chaisleáin, the walls of the castle)
Genitive plural:
caisleán, na gcaisleán (e.g. stair na gcaisleán, the history of the castles)

What does “caisleán” mean?

“Caisleán” has three alternative meanings. The most common comes first.

castle
A large fortified building, usually of stone, built in the past to defend a place or house a lord.Also: fortress, keep, stronghold.
2 other meanings: mansion or cumulus cloud
2mansion
A large, grand house, like a castle.Also: stately home, big house.
3cumulus cloud
A tall, piled-up cloud, especially in the phrase caisleáin óir for golden sunset clouds.Also: cumulus, cloud bank, sunset cloud.

Other Irish words for castle: caistéal (castle)

“Caisleán” with the article

The plural of castle in Irish is caisleáin. Here is caisleán after the article (an t-alt), in the singular and the plural.

an caisleán
the castle
No change after an
na caisleáin
the castles
Plural: no change after na

“Caisleán” in a sentence: Irish examples

Common Irish sentences using caisleán, the Irish word for castle.

Tá an teach cosúil le caisleán.
The house is like a castle.
Thugamar cuairt ar an gcaisleán inné.
We visited the castle yesterday.
Tá caisleáin go leor in Éirinn.
There are lots of castles in Ireland.
Bhí an rí ina chónaí sa chaisleán.
The king lived in the castle.
Thóg na páistí caisleán gainimh ar an trá.
The children built a sandcastle on the beach.
Tá ballaí an chaisleáin ag titim anois.
The castle walls are falling down now.

Other nouns in Irish

More everyday Irish nouns to learn next.

Castle in Irish: frequently asked questions

What is the Irish for castle?

The Irish for castle is caisleán (pronounced “KASH-lawn”). It’s a masculine noun and the plural is caisleáin. Depending on context it can also mean mansion or cumulus cloud.

How do you pronounce caisleán in Irish?

Caisleán is said like “KASH-lawn” (IPA /ˈkaʃlʲaːnˠ/).

What is the plural of castle in Irish?

The plural of caisleán is caisleáin; with the article, na caisleáin means “the castles”. The genitive plural is caisleán, as in stair na gcaisleán (the history of the castles).

Does caisleán have more than one meaning?

Yes. Caisleán can mean castle, mansion or cumulus cloud, depending on context; the first is the most common.

Why does caisleán change to chaisleán or gcaisleán?

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

What does 'caisleáin óir' mean?

Literally 'castles of gold', caisleáin óir means daydreams or castles in the air, and also golden clouds at sunset.

What is the difference between caisleán and dún?

Caisleán is a medieval stone castle, while dún usually refers to an older fort, often an earthen or prehistoric one.

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