I agree that nymph
would be a better answer to this clue but, since it had been explicitly discounted and didn't fit the given letters N?M?N, I thought that numen
was a possibility worth mentioning.
Numen is mainly (but not exclusively) associated with Roman - not Greek - mythology & culture but that could just be explained by a poor clue.
Etymology for numen
is given as: Latin, nod, divine will, numen; akin to Latin 'nutare' to nod, Greek 'neuein'
, so the Greeks certainly aren't out of the picture.
I wonder where the clue comes from? Is the same answer permitted for two clues?
If Jaycee could let us know and also give us the clue and crossing letters that led to the earlier ('other') answer nymph
it might make things clearer.