Multi-layered ecstasy pills. Commonly found at raves.
Wanna buy a triple-stack butterfly for $20?

Wanna parachute some stacks and roll for a few hours?
by addict7 June 27, 2006
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To fall down or crash whilst on bicycles, scooters, scateboards, etc.

Australian colloq.
hey mate, did you see that guy who fully stacked it on his bike the other day?
by iamewy January 30, 2009
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