Meaning of “flop” - Learner’s Dictionary

flop

noun [ C ] uk us /flɒp/ informal
FAILURE

something that is not a success:

The party was a bit of a flop.
MOVEMENT

a movement towards the ground, or the noise someone or something makes as they fall down:

She fell onto the bed with a flop.

(Definition of “flop noun” from the Cambridge Learner’s Dictionary © Cambridge University Press)