1. a dive into water, landing flat on one’s front.
2. a commercial failure.

   “the film’s bellyflop at the box office is unsurprising”

In the 2016 Olympics,  Ilya Zakharov was the defending Olympic champion in the 3m springboard and out of nowhere he bellyflopped.  Let’s think about this for a second, he did everything that he needed to in order to make it to the Olympics. Is that a flop?

Does the one dive described as a bellyflop define him for who he is? NO!