Murray

Well, you can certainly tell someone to "feck off"! And you're right - it would be regarded as light invective - no offence intended or taken!

As to geographical distribution (and I'll make no comment on "Eire"!) , I suspect the RANGE of meaning used in Ulster is wider, whatever about the frequency. Not surprising, given the Scots element in some of its senses.

Boab
Yeah - I know the word from Burns, of course. What I'm curious about is the etymology, if known.

Regards