UrbanDictionary.com's abbreviation for 'definition'. See the 'new def' link at the top of the page.
I added a new def today.

Okay, okay, I DO sound stupid.
by Diggity Monkeez February 4, 2005
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Certain. First used by Run-DMC. Sort for definate.
by Ahmose July 31, 2003
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abreviation for the word definately, usually used by kids who are either way cool, or way lame.

the only way to pull of using the term "def" is to be the first one around to use it. if you're just copying someone, people might think you're lame.
Kara asked if the new guy was cute.
Emily repiled, "Oh most def! He's soo hot!"
by Kara April 25, 2005
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a cooler way to say "definetely", used frequently by potheads
1. "I'm def def wasted"

2. "You should def def call me back"
by Mr.Byrne July 14, 2008
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the uncool, lazy way of saying "definitely"
Hey Carly, i'm your best friend right?" "Yea! defs!
by DKO123 September 26, 2010
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IS short for definitive. Originated in NY, no doubt.

or
"#3 on your touch tone, D-E-F spells def" either Tak or Ryu of Styles of Beyond...
by Titanium October 6, 2004
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def- short for definatly
is it pos for someone to be def ser about something that is def not pos to be ser about
by kingss49 January 31, 2003
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