Craic

A common expression in Ireland is "what's the craic?".  It's pronounced "crack" and it's the Irish Gaelic word for "fun". 

So when you hear people in Ireland going on about "having the craic" it has nothing to do with any type of illicit drugs. 

Here's a YouTube video of a short interview with a few members of the band Kodaline where they share a few more Irish colloquialisms.

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