def

1 of 3

abbreviation

1
defendant; defense
2
deferred
3
defined; definition
4
definite; definitely

def

2 of 3

adverb

slang
: definitely
Oh, I'll def be there!
If the Ed Westwick tidbit wasn't enough to get you up to the roof, the luxurious pool def will.Katie Buckleitner

def

3 of 3

adjective

deffer; deffest
slang
: cool sense 7
… but just about everything else you need is supplied in Rap Trax, a do-it-yourself kit of def beats and prime rhythms.Shann Dix

Examples of def in a Sentence

Adjective of the rappers on the scene, he was definitely the most def

Word History

Etymology

Adverb

short for definitely

Adjective

probably alteration of death (from the phrase to death excessively)

First Known Use

Adverb

circa 1942, in the meaning defined above

Adjective

1979, in the meaning defined above

Time Traveler
The first known use of def was circa 1942

Cite this Entry

“Def.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/def. Accessed 26 Dec. 2024.

Medical Definition

def

abbreviation
1
defecation
2
deficient
3
definite

Legal Definition

def.

abbreviation
defendant
Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!