This is a slang term for blow job, made popular by the show The Backyardigans.
I needed some money last night, so I gave this guy a Wacky Tiki behind the bookstore on 5th avenue.

The Mysterious lifeguard offered to show Pablo the penguin and Tyrone the moose how to preform a Wacky Tiki.
by Dade Murphy December 18, 2005
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