Def'n/Etymology of "beard"

I was just talking to co-workers and they said that some hollywood starlet was a “beard”. I asked and got the defn’ that it meant she was a “sham” wife for a gay guy.
-is this term commonly used?
-can it apply to a “sham” husband of a lesbian?
Why “beard”? I can think of 5 words off the top of my head that would describe the situation better than “beard”.

Yes, a beard is any cover, which is how it originated–like a real beard, it covers things up and provides a disguise.

Gay guys are not considered very masculine.
Facial hair is seen as masculine. So, anytime a woman is seen with a man a lot, people assume they are having sex. This will make the guy seem more masculine, (bearded) i.e. straight.
Elaine on Seinfeld was once a “beard” if I recall correctly.

“Any major dude with half a heart surely will tell you, my friend–
Any minor world that breaks apart falls together again…”
-Steely Dan

but a beard is real, even if it is for a disguise. And often times it isn’t. I would think that “mask”, “wig”, or even “merkin” would be better terms.

Hey, no fair asking real question here! Moving this to General Questions.

Saint Eutychus