@Tjagain Looked in three Gaelic dictionaries all say that Sasanach means Englishman. Incidentally I got the spelling wrong in my earlier post. When I started learning gaelic the meaning was as someone said above anyone from south of the Highland line but it changed maybe 20 years ago.
You can check the meaning here on Stor data an online gaelic dictionary
I did a stag do in Edinburgh, with a load of blokes from the Peak District, we were mostly mid to late forties, anyone on here remember that. I and a few others bailed out at midnight, but the hard core that carried on were asked to a party by some young lasses who gave them an address, when they arrived at the address it was a “Help the Aged” shop. You’ve got to hand it to them that damned funny.