Frottage, or dry humping, is the act of achieving sexual pleasure with a partner or partners, whether naked or clothed, without penetration. Frottage is often used interchangeably with body rubbing (look: Body Rubbing). But here, Frottage will refer more exclusively to mutual genital rubbing without penetration. That is rubbing your crotch or cock against your partner’s.
Frottage can be a form of foreplay or a method on its own to achieve sexual gratification. Often young people will use frottage as an earlier stage of sexual intimacy before more explicit contact is pursued. Also, frottage can be done without getting undressed, which may be preferable in certain circumstances (e.g., not have a room available). Being clothed can aid to sexual arousal and stimulation. The great news about frottage is that on its own it poses no personal health risk.