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29.
def
Certain. First used by Run-DMC. Sort for definate.
Were the best most def.
by Ahmose July 31, 2003
 
30.
Def
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 06, 2004
 
31.
def
Short for definately, but often used sarcastically.
(Person A looking at a hot chick)

Person A: I think I have a chance with that babe.

Person B: Def dude.
by Matt0912 May 10, 2009
 
32.
def
Extremely good or talented, from the word "death".
That's a def tag up you got there.
by TFS July 24, 2005
 
33.
def
Word commonly used in place of "definetly"...most often heard when in the presence of Julie and Mandie
Julie- Getting drunk later, though?

Mandie- Def.
by Mandie February 18, 2005
 
34.
Def
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 03, 2005