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Used in MSN conversations, when you see/read/whatever something that is really hot/cute/sweet/nice etc.
MSNer 1: Hey! Check out this superhawt RyRo picture (:

MSNer 2: OMGAH! He's so cute!
by Jedi Master Luna August 14, 2006
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Nov 27 Word of the Day
A stupid person; it refers to the lack of surface area on an individual's brain. The general thought is that the more surface area (wrinkles, creases, etc.) a brain has, the smarter the person is. Conversely, a person with a smooth brain (no wrinkles) has less surface area and would therefore be stupid.
That fucking smooth brain put his shirt on backwards again...

That smooth brain is dumber than a pile of shit.
by Tip Tank May 14, 2011
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an exultation expressing extreme excitement or surprise in a particularly pleasing situation; can also be used to replace the phrase "holy shit!"
Thing 1: Have you seen "The Shawshank Redemption"?

Thing 2: "OMGAH! I LOOOOVE that movie!"
by Youwishi'dtellyou June 18, 2008
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