The act of motorboating applied to a scrotum.
"She scrotorboated me when she went down on me last night"
by ShiftyJack November 25, 2009
Verb: to motorboat someone's ball sac as though it were a woman's cleavage. Scrotorboating is not exclusive to the nuts, and can even include said activity on someone's taint.
"Please just go down on me. When you scrotorboat me, it tickles and I lose focus!"
by FeralBuddy October 13, 2011