A prehomosexual is a person, usually a child, who may be a homosexual but is either undecided or predetermined. A study by J. Michael Bailey and Kenneth Zucker suggests that prehomosexuality may be recognized from "inverted pattern[s] of sex-typed childhood behaviors", such as boys interested in makeup or girls interested in sports. However this ciorrelation is not perfect.
References
Prehomosexual Wikipedia(Text) CC BY-SA