The act of Tennis Kissing is where one repeatedly kisses two people back and forth like in a game of Tennis. This generally promotes a threesome which happens soon afterwards.
Male1: That tall blonde tennis kissed Geordie and Jacob last night
Male2: Wow, did they have a threesome later?
Male1: Nah, they proceeded to spit on unsuspecting people while on the dance floor and lost track of the girl while doing so.

Tennis kissing saves lives
by DriverD April 7, 2014
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