Top definition
The yellow sac pustules that you cough up and whe you squeeze them they pop open and emit a horrible smell
Alan coughed up a Lung Mustard and he poped it in my face. The smell just about made me throw up
by steve April 29, 2003
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