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A sex act in which a girl grinds her bare or covered pussy against her partner's penis without being penetrated.
This is different from imminent vaginal. There, the head of the penis is directed at the vaginal cavity with the intent to penetrate. Here, the female's pussy is simply rubbing against the penis without actually penetrating. The key visual difference is that the penis is more or less directed in a horizontal position against the pussy so that it can't penetrate like the vertical position can.
For ass-to-penis rubbing, use buttjob instead.
For pussy-to-object rubbing, use crotch rub instead.
For pussy-on-thigh rubbing, use thigh straddling instead.
For pussy-to-pussy rubbing, use tribadism instead.
For penis-between-thigh rubbing, use thigh sex instead.
For rubbing against anything else, use frottage.
If both participant still have clothes use dry humping instead. If the girl is using an object to rub her crotch instead of a penis, use crotch rub. If no sex is involved and someone is grinding along an object with any kind of skates, use sliding instead.
See Also
The following tags implicate this tag: double_grinding (learn more).