When a man encounters an obese woman who's back fat creates the illusion of boobs, and the man proceeds to shake his face between the "boobs" while making the sound of a motorboat with his lips.

The motorboating of an obese woman's "back-boobs."
See that sweaty, fat chick over there? I'll be boatermoting that back fat like a Louisiana swamp boat captain later tonight.
by BrentJones84 September 27, 2014
Get the Boatermoting mug.