A man, often but not always gay, who favors the stereotypically lesbian lifestyle, i.e., Birkenstocks, sandals, long scruffy hair, recycling, vegetarian pot-lucks, child-raising, etc. as oppossed to circuit parties, gym memberships, promiscuity, and fashion etc.
Remember that show "All in the Family"? Gloria's husband, Mike, a.k.a. "Meathead" was a real *guy-dyke*.