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:
对接: mutual masturbation by inserting the glans penis into the foreskin of another penis.
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The docking and berthing of spacecraft roughly refers to the joining of two space vehicles. Docking specifically refers to joining of two separate free-flying space vehicles.
A docking/berthing connection is referred to as either "soft" or "hard". Typically, a spacecraft first initiates a soft dock by making contact and latching its docking connector with that of the target vehicle. Once the soft connection is secured, if both spacecraft are pressurized, they may proceed to a hard dock where the docking mechanisms airtightly seal together, enabling interior hatches to be safely opened so that crew and cargo can be transferred.
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The act of placing the head of ones penis inside the foreskin of another's penis.
David and Patrick enjoyed docking immensely because of Patty's stretchy foreskin.
Source: Urban Dictionary
Where one places the head of their penis into the foreskin of another, so that the two heads touch and rub.
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