Dictionary.com

def

1
[ def ]
/ dɛf /
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adverb Informal.

definitely: Going to Europe this summer? But def!

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Origin of def

1
By shortening

Definition for def (2 of 3)

def2
[ def ]
/ dɛf /

adjective

Slang. excellent: That hip-hop record is def!

Origin of def

2
An Americanism dating back to 1980–85; of uncertain origin

Definition for def (3 of 3)

def.

abbreviation

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2021

Example sentences from the Web for def

British Dictionary definitions for def (1 of 2)

def
/ (dɛf) /

adjective

slang very good, esp of hip-hop

Word Origin for def

C20: perhaps from definitive

British Dictionary definitions for def (2 of 2)

def.

abbreviation for

definition
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Medical definitions for def (1 of 2)

def

abbr.

decayed, extraction indicated due to caries, or filled (used for deciduous teeth)

Medical definitions for def (2 of 2)

DEF

abbr.

decayed, extraction indicated due to caries, or filled (used for permanent teeth)
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
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