mos def! 

short for most definetly!!!!

tyler: Did it feel the best when i put it in your butt last night?

zane: mos def!

mos def! by jake1234 April 23, 2006

mos def 

a fly MC, often apperaring alongside Talib Kweli, The Roots, or Common

mos def is one ill nigga, son

mos def by Ponyboy August 3, 2003

mos def 

Slang for 'most definitely'

"Wan' a cig, man? "Mos' def!"

mos def by David Allison August 21, 2003

mos def 

A man who can not only act with 5 star ability, but can also create some of the best shit out on recording ever.

Mos Def yet an actor of decent fame still keeps his hip-hop true.

mos def by Paul October 2, 2003

mos def 

(adv.) meaning: most definitely; the phrase also pays homage to the infamous emcee, Mos Def.

"You better hit me up with those tracks."
"I'll mos def hit you back, hommie."

mos def by kduballstar October 6, 2005

mos def 

1.: A slang term for "most definitely."
2.: A rapper.
3.: Deaf - this useage is the least common, mostly by people who didn't understand it in the first place or mispronounced.

1.: "Am I going to the party? Mos def!"
2.: "Mos Def is one of the best rappers of our time."
3.: "After that concert, they're mos def."

mos def by Gillian January 4, 2005

Mos Def 

Mos Def is many things. In everyday lingo, Mos def is an abbreviation that can mean "Most definitely"(1) wich originated from the ghetto but like every other gansta term has evolved inti something widely used by young and filthy rcih white kids.

Mos Def in the music and film industry is the pseudonym of Dante Smith(2). Quasi legendary emcee who's soulfoul approach to hip hop and unique style has made him one of hip hops heavy hitters. He and Talib Kweli are known to collaborate alot, even making Black Star. Mos Def is also a pretty good actor who appeared in the remake of "The Italian Job" and the still in production "The Hitchikers Guide to the Galaxy".

Last a probably least, Mos Def is a brand of urban clothing(3). Most of they're stuff is pretty basic, but pretty cool. Hell, I'd pay for a sweatshirt that says "Mos Def"

Last and probably least,

1-Crack Peddler: "HEY BITCH! You wanna suck my cock for a crack rock?"
Crack Whore:"Mos def!"

2-Man Mos Def is ill, but he was really pushing his luck with his newest album.

3-Guy 1:Hey look, is that a "Mos Def" brand sweatshirt?

Guy 2: *Looking at sweatshirt clearly labeled "MOS DEF"* man, you're lucky I dont have my trusty 2 by four to beat yo ass.

Mos Def by mrpopenfresh March 5, 2005