Nothing is perfect! Its not possible. There is always a fault or something that can be improved. "Nine Nine" means as close as it gets to perfect. AKA 99%.
"Do you know Andy? That kid is nine nine!"

I had a real nine nine day today at work.
by Jamie Westwood July 30, 2004
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a catchphrase used by the CUTEST groups of humans ever, it symbolize their precinct; the nine nine. it’s their way to show how they are together, forever.
terry: nine nine!

everyone else: NOINE NOINE

me: crying
by nineninethings January 27, 2019
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Slang used to say 79th street in Chicago
we on the nine after school
by cam da one February 11, 2007
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To do something frequently.

Derives from local television and radio stations doing their traffic and weather "on the nines"
- Mike, you smoke weed?

- On the nines, man!

I get head on the nines, but for some reason I never have sex.
by Don't Hurt Um October 8, 2009
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Not the definition of the "girth" of the barrel, but rather it's bore - the width of the hole that goes through the barrel. Also, not coincidentally, the diameter of the bullet - 9mm.

Refers to a pistol, usually a semi-automatic, ostensibly a 9mm.

Aside: The U.S. Army's standard pistol is a 9mm semi-automatic.
by Rob Hruska February 6, 2004
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Nickname for girls rated 9 out of 10. The word is typically used by dudes lacking self confidence, and therefore would not deserve "10's"
"Make sure you invite those NINES to the potluck tonight and bring your gamefaces"
by Nipples Gurunt December 12, 2008
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