Muliebrity.

It is a great thing now to have, if not exactly an antonym, at least counterpart to virility.

I wonder what is the proper term for such terms. We can agree that love and hate are antonyms; energetic and listless are antonyms. But 'boy' isn't really an opposite, is it, of 'girl.' Yet they are biologically different. Same goes for application of virility and muliebrity. I wonder whether there is a term to show these counterpoised relationships in things that are in different classes, yet not exactly antonyms?