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1 definition by TrinityHH

Analogous to "fisting", capping is the act or art of inserting a bent knee into a vagina (this may require vast amounts of lubrication). Upon completion, the 'capper' may straighten out their leg to remove the knee from the 'cappie's' orifice.
"I saw this capping video on the net ... the whole damn knee was inserted in her!"
by TrinityHH June 24, 2007