when a girl puts that delightful arch in her back, and sticks her ass out in a erotic/sexually suggestive manor, often accompanied by a "booty dance", that brings shear delight to the males species.
"did you see her back that ass up, playboy? it almost brought a tear to me eye, and a 2x4 to my pants!"

"did you see lucy liu bending over in the drive-thru scene in charlies angels?? ddaaaaaaaaamn, it was delightful! that the essence of female perfection!"
by deluks November 30, 2005
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1. Back the fuck up. Get out of my face. Calm Down
2. Insist a female shake and rub her ass against you when dancing.
1. Damn nigga, back that ass up before I get crazy up in here.
2. Come here girl and back that ass up for me.
by Phatty Mcgatty March 28, 2004
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Song that you sing to guys with big tank asses that pass your lunch table
Whoo Whoo, sweet ass Bojangles, you's a fine mothafucka won't you back that ass up
by Anonymous March 10, 2003
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when a guy sees a female that he finds attractive and most likely with a ghetto booty....he will call to her by saying this
hey you....dont do me like that back dat ass up
by *~Desiree~* July 20, 2004
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