A phrase used in elementary school to pressure someone into a situation. After the dare has been declined the person "daring" the other will try to take it to the next level. The origin is unknown but is commonly believed to have made it's debut in the movie "A Christmas Story". Use before going to the Triple Dare, Triple Dog Dare, and then if all else fails revert to cursing.
Flick: Are you kidding? Stick my tongue to that stupid pole? That's dumb!
Schwartz: That's 'cause you know it'll stick!
Flick: You're full of it!
Schwartz: Oh yeah?
Schwartz: Well I Double Dog Dare ya!