Epicene (< Latin epicoenus < Greek epikoinos 'common to many, promiscuous') originally meant 'having the characteristics of both genders (both in the sexual and grammatical sense), and effete, as tsuwm's post showed, meant infertile. In linguistics, epicene nouns are ones in which the male and female terms for animals are the same, not different. They are both roughly synonymous in English in the meaning 'an effeminate (man)'.

Ceci n'est pas un seing.