Homologue is not strictly a sex word, but it is a useful word to understand in the context of the study of human sexual anatomy.
If two things are homologous, they are corresponding or alike. So in sexual anatomy a homologue is a structure that equivalent to a similar structure in the other gender.
Eg. The clitoris is the female homologue for the penis,
OR the clitoris is the female equivalent of the penis.