look up any word, like swag:
 
1.
A common condition where someone makes repeated grammatical errors, often followed by hysterical laughing and joking. The only cure for brain-weasels is to suffocate them by smothering the victim with a pillow.
Crap, you're infested with the BRAIN-WEASELS! Quick, smother him/her with a pillow.

*followed by a small footchase and a pillow smothering*
by Noah February 01, 2005
6 5