OS Impurum

Some articles on os impurum:

Sexuality In Ancient Rome - Sex Acts and Positions - Os Impurum
... Os impurum, "filthy mouth" or "impure mouth", was a term of abuse especially for those who provided oral sex ... An accusation of having an os impurum is an "extreme obscenity," so vile that Cicero reserved it for men of lower standing than himself, only implying that their debasement tainted their more ...