Gender (female) specific variant of
actor.
Not PC--considered to be
sexist language.
Note that many theatre programs (e.g: UC Davis) no longer use the term actress, but instead uses actor to refer to actors of both genders.
In Metamagical Themas, Dogulas Hofstadter discusses sexist language, including pronoun issues--briefly stated: The use of a feminine specific in the absence of a gender neutral prevents the male specific from devolving into a genuine generic.