Top definition
It comes from "my bad" when you make a mistake, "my dumb" is when you did something dumb.
Shannon "No, it's not me it's the other Shannon."

Chad "Oh sorry, my dumb!"
by Zilla December 13, 2004
Mug icon

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