Definition Of belly flop
a commercial failure.
the film's bellyflop at the box office is unsurprising
a dive into water, landing flat on one's front.
He teetered, lost his balance and fell off, making a tremendous splash as he hit the water with an inelegant bellyflop and an angry shout.
perform a bellyflop.
The two men bellyflop each other for a bit until Haystacks falls through the ropes on to a nice ringside flower arrangement and is counted out. ‘Easy!