A variation on the classic motorboat technique (see below) normally applied to breasts, the Larsen Outboard is instead applied to butt cheeks.

Motorboat: The act of pushing one's face in between two ample breasts, and rocking one's head side to side very rapidly while making a vigorous, lip-vibrating "brrr" sound.
Moosy (Larsen) asked Steady to cook him a cheeseburger.

Steady replied, "Sure, right after you finish motorboating my butt cheeks."

A loyal friend and hungry for a cheeseburger, Moosy obliged him with a Larsen Outboard.
by zhakespeare March 15, 2010
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