To throw in my tuppence - MANY people - myself included - use the term "Celtic" to describe music (strict traditional and folk, or music based on those origins) of Scottish, Irish, Manx, Welsh, Breton, Cornish and Galician origin. Whether or not this is strictly correct based on academic arguments, I don't care - it is a matter of convenience.

If, however, you mean "Irish" or "Scottish" music specifically - then say so.

There are a large number of people who do Irish or Scottish music trapesing about in psuedo-historical dress playing 12 string guitars who describe themselves as Celtic. I prefer "silly" as a handle for those folks.

Getting off the soapbox now.

Pete