N-UNCOUNTLesbianism refers to homosexual relationships between women or the preference that a woman shows for sexual relationships with women. 女同性恋关系; 女同性恋取向
例：
...today's increased public awareness of lesbianism.
This, combined with the trivial observation that not all lesbians have twin brothers, suggests that if male hormones are inducing lesbianism, they are coming from elsewhere.