Acronym for Lesbian Until Graduation, i.e.: a woman who experimented with bisexuality or homosexuality at university, and who subsequently changes their sexual orientation when they have discovered their true identity, or otherwise hides it to avoid discrimination or harassment. Regarded as a derogatory term used against them by their more committed sisters.
The slang word was identified by New York Times writer Sara Rimer in the article "Campus Lesbians Step Into Unfamiliar Light," published June 5, 1993.
A more general word for such women is hasbian.