an otherwise straight person who works for gay rights and is interested in gay history and culture. Kinda the flipside of gay people who beleive homosexuality is an illness. Straight allies are most often found in organizations like Gay-Striaght Alliances and Parents and Friends of Lesbians and Gays, and often more passionate about gay rights that some gay people. Some are related to homo/bi/trans etc. people, some are freinds, and some are commited to equality and fairness.
a Straight Ally is the "A" in LGBTQA. I'm a Straight Ally