transitive verb flopped, flopping flop′·ping

1. to flap, strike, throw, or cause to drop noisily and clumsily
2. Photoengraving to turn (a film negative) face down before exposure to a metal plate, in order to create a desired mirror image

Etymology: echoic var. of flap

intransitive verb

1. to move or flap around loosely or clumsily, usually with a thud or thuds
2. to fall or drop in this way to flop into a chair
3. ☆ to make a sudden change
4. Informal to be a failure
5. ☆ Slang to go to sleep

noun

1. the act or sound of flopping
2. ☆ Informal a failure
3. ☆ Slang a place to sleep
4. Slang dung or a piece of dung cow flop

adverb