Definition 1: When a bunch of dirty skanks jump out of an airplane, and they have a bunch of dirty coochies and their parachutes are hanging from their clits.
Definition 2: When a girl uses her vagina curtain as a chute after jumping off a building or cliff. The equivalent of base jumping. Also see: vagina curtain
Example 1: Jennifer, Chloe, and Mary went clam jumping last weekend. Their chutes got tangled, and tore out their vaginas. Ouch!
Example 2: Beth went clam jumping off the Empire State Building by using her vagina curtain as a chute.