Goidelic languages
In all modern Celtic languages the term for Easter is derived from Latin. In the Brittonic languages this has yielded Welsh "Pasg", Cornish and Breton "Pask". In Goidelic languages the word was borrowed before these languages had re-developed the /p/ sound and as a result the initial /p/ was replaced with /k/. This yielded Irish "Cáisc", Gaelic "Càisg" and Manx "Caisht". These terms are normally used with the definite article in Goidelic languages, causing lenition in all cases: "An Cháisc", "A' Chàisg" and "Yn Chaisht".