The only country that would almost fit - if the 's' was an 'a' would be Grenada & that's not Gaelic.
Have another look at that s. What was the clue and answer?
WISHED would do the trick but only, of course, if the clue read "DESIRED Calendar Girls"
But that messes the wordplay: WI is ok, but SHED (or SHE'D) does not cut the mustard as well as SHE'S. You are right, I'm sure.
Ireland (Gaelic!), Iceland, Wieland & Seeland (the largest island of Denmark and the site of Copenhagen) are the only near fits. Can't think of any country ending in 'S'...
I think the Irish Gaelic for 'country' is duithe, and it's similar in Scots Gaelic (duitheach or a variant spelling), but you might be on to something there: it might have been a Gaelic name for a specific country in the same ways as Alba was the old (Irish Gaelic) name for Scotland.
Then Gaela?s begins to have a certain appeal, but I cannot verify it anywhere or find a suitable missing letter..
Just a suggestion - I'm stumped in all truth!
'Glenans' fits, which refers to some islands in Brittany and is also the name of an Irish sailing school. By some stretch that (Brittany) could be called 'Celtic' but hardly Gaelic... Is the crossword usually this hard or are we complicating this clue?
Thanks chrysaor. The crossword is "The Wee Stinker" in The Glasgow Herald (Monday), said by many to be the hardest and most devious crossword there is.