The sound and feeling male genitalia makes when running naked. Can be quite painful depending on how cold it is.
After streaking across the field Joe remarked "Man, I've got some nasty flippety-flop."
"The only downside to streaking is flippety-flop."
The Urban Dictionary Mug
One side has the word, one side has the definition. Microwave and dishwasher safe. Lotsa space for your liquids.
Buy the mug