Castle is caisleán.
Trim Castle
The Irish Gaelic for 'castle' is is caisleán (sounds like cash-lawn).
The Castle is built on a large rock at the edge of the town of Cashel in Ireland. Caisleán is the Irish word for Castle and this would be the origins of the name Cashel.
Caisleán
Carrickfergus Castle is wrong its Ballynahinch Castle
Ballynahinch Castle
Co. Mayo
caisleán ['cashlaun']
Your in Irish Gaelic is: bhurthe Irish word for your is: bhur
It is an Irish word.
The Spanish surname Castillo (also Castilo) is from the Latin castellum, meaning castle (fortified building).
Ballynahinch Castle