Now I think of it, I considered that definition of the answer yesterday and dismissed it as too imprecise. I see now it is in Chambers but, as happens with some setters, it's one of the later definitions, the other three being much the more common meanings. This clue actually had three obscure references, which I consider a poor clue. I find clues that challenge interpretation more rewarding and a better testament to the setter's skill than those that keep sending you to the dictionary.