A substance inexplicably present at meetings between close, air-brained math class friends. Also, can be used as a wild card sort of word, when words just don't come to mind but your lips keep moving.

Associated motions: Jazz fingers, followed by a quick jerking "yesssss!" motion with both fists, is commonly understood as sign language for the phrase.

The "Purple Shit" is the official name for the large, and violet McDonald's character.