Also known as Jeong Yoon oh or Jung Jaehyun. Someone needs to give him cake cause everyone knows that he doesn't have one. Jaehyun is the king of all Flat Asses.
Heres how you would use it

Random person : Whats a Flat Ass?

Czennie : A flat ass is someone without cake also known as Jung Jaehyun.
by sochenle April 3, 2021
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A re-working of the expression flat out. Ultimate or distinguished from others by a high concentration of the quality expressed
She is flat ass beautiful
by morie October 23, 2005
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An insult normally directed at a fat girl wearing tight clothes aiming to make the most of her assets. This girl normally possesses the required saggy jelly tits in an undersized bra, saddle bag thighs, extra wide hips and a balloon belly gut, however her back tends to run directly into her upper thighs without so much as a ripple. Giving the impression that her lower body is the wrong way round.

This insult should be used carefully if the intended target is within earshot and of African descent as you will probably become the victim of a violent assault. Directing this insult at a Caucasoid female is a lot less dangerous as it may be taken as a compliment.

Other noted recivers of this insult are:

i)Skinny girls. Ususally wearing very big or string type belts in the hope of creating a feminine figure

ii)White guys. Who reputedly all have a flat ass, even the fat ones.

iii)Black guys. Displaying the opposite of the Arsenio Hall afliction
The scene: A club dance floor.. a DJ spins Baby Got Back and the more ample figured ladies stampede to the dance floor. Two friends who narrowly missed being trampled take refuge in the corner and watch.

Friend 1 turns to his buddy and observes "look at that flat assed hoochie mamma trying to shake what she doesn't have"
by jasonlondon August 3, 2006
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An ass that is flat,noncurvaceous. Common among Asians.
Look at that flat ass! There's no meat in there!
by Bobby De Niro January 6, 2006
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An old school slur for white guy used most notably by Richard Pryor.
White guy: "Exscuse me, but do you know where I can find a liquor store and a KFC?"

Black dude: "Fuck you flat ass!"
by Aaron Brace October 25, 2005
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flat asses are now popular amongst black women......
not to many black women have big asses most women in the world have flat asses mostly black and white girls.
damn that bitch got a (flat ass).

flat cardborad look like shit
by Lee_Lee dat girl October 20, 2007
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