1a. Clue Sympathy (13) I have commiseration. So I figure it wouldn't end in an 'a'. I have just found a word nasute which I think is discerning of smell?
nasute is a termite in my dictionary but apparently I choose to us ethe wrong dictionary (joke for Naomi if she's ventured into crosswords thinking it said cross swords); but this site seems to back up the discerning meaning https://www.wordnik.com/words/nasute