Still, today, frot is rarely used, and if so, generally only means "to chafe" or when one is dancing with another, "to gyrate."
How the gay community adopted this term is a mystery. Why they would choose such a disgusting sounding word to describe a sexual act is another mystery. If they wanted the act to be taken seriously, a more proper word should have been chosen, as "frot" is incorrect.
"Fricitation" and "frontism" are the correct terms for what the gay community think of as "frot." Genito-genital rubbing or GG rubbing is a term frequently used by primatologists to describe the act. "Frotting" simply means "chafing."
Dave: Would it be a sin to frot that girl over there subway doors?
Sean: I wouldn't. I saw her frotting four dudes at the club last night. She probably gets around.