Anytime one person says something silly or dumb that everyone around them knows to be true or fact about the person talking.
Senario 1:
Me: Man I'm sleepy.
You: Your always sleepy.
Me: I'm going to have to give you a duh on that!
Me: Man I'm sleepy.
You: Your always sleepy.
Me: I'm going to have to give you a duh on that!
by Evilness666 November 14, 2005
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