A "beard" in the sense of an opposite-sex escort to give the illusion of a heterosexual couple is a homo (and hetero, actually) sexual slang term that has been around for quite a while. The Dictionary of Contemporary Slang dates it to the mid-70s, but I think that, at least in New York City, it may go back to the late 60s. The DSC, to my surprise, tags it as a male escort (for a woman), but that's wrong. A beard is usually a female escort for a man; the male equivalent (for a woman, not necessarily a lesbian) is a walker.
-alga-