Genital-Genital Rubbing

Genital-genital rubbing (often termed GG rubbing by primatologists to describe the behavior among female bonobos) is the sexual act of mutually rubbing genitals; it is sometimes grouped with frottage, but other terms, such as non-penetrative sex or outercourse, are also used:

Intercrural sex, or interfemoral sex: the penis is placed between the partner's thighs, perhaps rubbing the vulva, scrotum or perineum.

Frot or frottage: two males mutually rubbing penises together.

Tribadism or tribbing: two females mutually rubbing vulvae together.

Docking: mutual masturbation by inserting the glans penis into the foreskin of another penis.