n, v. The act when one man buries his face in between another man's buttocks and vigorously throws his head back and forth while resonating his lips to make a "brrrrr" sound. Very similar to motorboating.
I almost passed out with delight when Henry knelt behind me, buried his face between my naked ass cheeks, and gave me a Sebago Speedboat.
The sound one makes by placing his or her face in cleavage and shaking their face back and forth while exhaling creating a "brrrrrrp rrrrp rrrrp rrrrp" sound.
The hummer she gave me was so good, I gave her a speedboat as my way of saying thanks.