This is basically a slang word for booty, it's cool to use because people won't know what your saying or talking about.besides the girl your talking about wont know too
Boy:that girl has a mega big Nyash

Girl:boy,what you talkin 'bout what's nyash
by ------queen October 5, 2019
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a way to describe the perfect bunda (bum) of a girl, and how you wanna jeet that nyash
boy: wys babes, you got a big nyash yk
Girl: awh thanks, wanna do a quickie rn?
by VlxneM1 March 28, 2022
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