Tribadism
Tribadism (trib'ad-izm) [G. tribein, to rub, + -ismos, condition] is a sexual practice where two women rub their external genitalia against one another for clitoral stimulation. For this reason, lesbians have sometimes been referred to as tribades. Also known in the vernacular as donut bumping or monkey bumpin' and bumping uglies.
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