Top definition
The little balls of deodorant that form under the armpit from applying too much or, for those who choose not to shave, from having too much pit hair.
Chris: Hey man what is this under my pit! I have lint.

Steve: Oh no dude that's underarm armor, you are now forever protected from the evil perspiration monster.
by Mrs. shaky bacon December 08, 2009
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