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def

1 American  
[def] / dɛf /

adverb

Informal.
  1. definitely.

    Going to Europe this summer? But def!


def 2 American  
[def] / dɛf /

adjective

  1. Slang. excellent.

    That hip-hop record is def!


def. 3 American  

abbreviation

  1. defective.

  2. defendant.

  3. defense.

  4. deferred.

  5. defined.

  6. definite.

  7. definition.


def. 1 British  

abbreviation

  1. 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

def 2 British  
/ dɛf /

adjective

  1. slang very good, esp of hip-hop

"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

Etymology

Origin of def1

By shortening

Origin of def2

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

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

After signing to Def Jam Records, the rapper launched his own solo career with the platinum-selling The Great Adventures of Slick Rick.

From BBC

By spending a new hour looking back at a bygone period, specifically the ’90s, when Wayne grew up, the 38-year-old comedian is bringing a fresh approach to the Def Comedy Jam era that he hopes resonates with comedy fans of his generation and younger fans who found him through TikTok and had no idea he even did stand-up.

From Los Angeles Times

"If you're looking for a mental break from the world def get Pokopia, it's like therapy," US-based influencer Ashley Duncan wrote on X.

From Barron's

“Mutt would make you do everything again and again until he thought it was good,” says Joe Elliott, Def Leppard’s frontman.

From The Wall Street Journal

Def Jam, the influential US record label, will launch a division in the "capital of Chinese hip-hop" Chengdu, its parent company Universal Music announced late Tuesday, in a vote of confidence for China's music scene.

From Barron's