Top definition
When you are so certain of something, that you will suck dick if you're wrong. Only works for guys.

Generally used to stop innane arguments when one ignorant person keeps arguing something they know nothing about and you know that you're right.
"Isn't the Pub on the next street?"
"No, dude, it's on this one."
"I'm sure it's on the other street."
"Well, I'm SD Sure it's on this one."
"Whoa. Okay, then. First round's on me."
by Frogman Tim3 November 12, 2009
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