geographically speaking Irish Music is from the British Isles (as opposed to British) but I doubt that many Gaels would speak of it thus. Celtic suits me as a generic term. What about music from Cape Breton Island? If that is not Celtic despite the flavour and origin and culture then I'll be hornswaggled.
What'll you be?
**BTW** ask any casual passer-by and they would call it Irish music because a) it is a session b) it goes diddly dee c) unless they are into it they pick-up on the similarities when we KNOW the differences.