A shortened version of "Shuuuut the fuck up."
My boyfriend and his friends would constantly tell each other to shut the fuck up...so often, that they shortened it to "Shaaat." Their rules also state that the more you mean it, the longer you say it.
If someone you know talks incessantly, then you would say "Shaaat!"

If someone asks you to borrow an insane amount of money then this would be a time to use the extended version..."Shaaaaaaaaaaaaat!"
by The Midg May 17, 2004
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The slick way of saying shit.
Shaaat she ugly.
by LaDy..WiLdCaTs October 29, 2008
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