- The definition of def is a slang term that is excellent or first-rate.
An example of def used as an adjective is in the phrase "that music is def," which means the music is excellent.
def definition by Webster's New World
Slang excellent; first-rate
Webster's New World College Dictionary Copyright © 2010 by Wiley Publishing, Inc., Cleveland, Ohio. Used by arrangement with John Wiley & Sons, Inc.
def definition by American Heritage Dictionary
adjective def·fer, def·fest Slang
Origin: Short for definite.
abbreviationThe American Heritage® Dictionary of the English Language, 4th edition Copyright © 2010 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
def - Medical Definition
decayed, extraction indicated due to caries, or filled (used for deciduous teeth)
decayed, extraction indicated due to caries, or filled (used for permanent teeth)