The 666th sense is esp that lets you know when your significant other is lying, cheating or otherwise behaving like the antichrist. Related but not to be confused with having 6th sense.
guy 1: Man, how does your girlfriend always know when we were at the strip club
guy 2: It's her 666th sense.
guy 1: damn.
guy 2: It's her 666th sense.
guy 1: damn.
by brandy_1013 September 21, 2007