Latin for male prostitute. As far as I know (and I am no scholar of Latin by any means) this is the only feminine noun referring to a masculin subject. Apparently the Romans did not like the sound of "-int" and words containing this combination ended up having negative or derogatory meanings.
"The Interocitor is an alien communications device with unusual and strange properties. The concept was invented by science fiction writer Raymond F. Jones, who wrote the original novel This Island Earth beginning as a series of three sci-fi short stories now known as “The Peace Engineers Trilogy�? appearing in the sci-fi pulp magazine Thrilling Wonder Stories from 1949 to 1951." -Wikipedia. Made into a movie, This Island Earth" was popular in the fifties and has become cult classic.