A mispelling of the word crack. The word originates from the Anglo-Saxon term, "crack" meaning fun.

It possibly dates back as far as Old English or the older Scots dialect and is still used today by Ulster-Scots in northern areas of Ireland.

Borrowed by the Gaelic Irish and spelt "craic", the term has been picked up by UK journalists in recent years and has re-entered the use of the word in mainland UK, however Dublin journalists in the 1970s frequently spelt the word as "crack" in written articles.
What's the crack?
Aye it was good crack!
To craic crack a joke

by G Holliday April 5, 2006
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