Epicene

Epicene \EP-uh-seen\ , adjective;
1. Having the characteristics of both sexes
2. Effeminate; unmasculine
3. Sexless; neuter
4. Linguistics: Having but one form of the noun for both the male and the female
noun;
1. A person or thing that is epicene
2. Linguistics: An epicene word

This word, formerly epycen, dates to the mid-15th century as a grammatical term for nouns that denote either gender. It comes from Latin epicoenus ("common"), which is derived from Greek epikoinos ("common to many, promiscuous"). The Greek word is a combination of epi + koinos ("on" + "common"). The rest of the definitions date to about 1600 except for "effeminate," which is first attested in the 1630's.

Today's word and the first definition were both taken from Dictionary.com's 'Word of the Day' for Friday, March 11
Etymologies come from the Oxford English Dictionary and/or Etymonline.com