\ ˈdef \
deffer; deffest

Definition of def

 (Entry 1 of 2)


Definition of def (Entry 2 of 2)

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

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Synonyms & Antonyms for def

Synonyms: Adjective

au courant, cool [slang], downtown, groovy, hep, hip, in, mod, now, trendy, turned-on, with-it

Antonyms: Adjective

out, uncool, unhip, untrendy

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Examples of def in a Sentence


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

Recent Examples on the Web: Adjective

The worst part about all of this is def the lyrics, though. Carolyn Twersky, Seventeen, "Noah Cyrus and Lil Xan's New Music Video Just Leaked and It’s Painfully Awkward To Watch," 17 Sep. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'def.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of def


1979, in the meaning defined above

History and Etymology for def


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

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Learn More about def

Statistics for def

Last Updated

25 Nov 2018

Look-up Popularity

Time Traveler for def

The first known use of def was in 1979

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More Definitions for def

Medical Definition of def

1 defecation
2 deficient
3 definite

Legal Definition of def.


More from Merriam-Webster on def

Thesaurus: All synonyms and antonyms for def

Comments on def

What made you want to look up def? Please tell us where you read or heard it (including the quote, if possible).


someone who never drinks alcohol

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