It can mean so what. It is like saying I told you so. It is proving somebody wrong.
My brother: you can't get off that phone in a half an hour. Me: I got off in 10 min. AND WHAT !!!
by Dennis September 28, 2004
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A term commonly used after a successful comeback.
Guy "Thats not what your mother said to me last night!"

-Short pause for comeback, if no comeback, you then precede to say...

Guy "AND WHAT!"
by Costeenius November 28, 2009
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Roughly equates to "so what". Can also mean absolutely nothing, depending on the context.

Context usually found in England, or at least London, is during the build-up to a fight in order to start something.
And what? You startin? And what?
by Someone else March 23, 2005
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A filler phrase that's short for "and whatnot," which is/can be used as an ending to a sentence or s statement.

This can also mean and shit, and stuff, and all that shit, etc.
We just coolin' out and what.
by Mr. Terrence L. Trezvant April 29, 2007
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Short for 'And what are you going to do about it'
ME: i don't like you
Stupid head: and what?
ME: and ... you better back off before your
nose and your eyes become one of the same
by broder October 19, 2005
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A phrase a certain race uses as an excuse for a good comeback.
Me: You're so ghetto, you use extention cords running from your neighbors house to your trailor.
Dumbass: And what?!
by Richy Rich March 03, 2005
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