EPICOENE, in grammar, a term applied to nouns, which,

which, under the same gender and termination, mark indifferently the male and female species. Such in Latin is quila, vespertilio, &c. which signify equally a male or female eagle or bat.

Grammarians distinguish between epicene and common. A noun is said to be common of two kinds, when it may be joined either with a masculine or a feminine article; and epicene, when it is always joined to some of the two articles, and yet signifies both genders.