def

noun

1. (abbreviation, alt-of)Abbreviation of definition.

   “In that case Wills, J., adopted a dictionary def of “Cowkeeper” as, “one whose business it is to keep cows,” and added, “the business of a Cowkeeper is a special business of its own.””

   “The Black Books also reflect [Philip Babcock] Gove’s notoriously brusque manner, no doubt gained from an early career in the Navy. Memos begin, “Editorializing has no place in definitions,” or “Godlove’s psychophysical defs of color names and their references had better be regarded as sacrosanct.” Sir, yes, sir!”

2. (abbreviation, alt-of)Abbreviation of deficit.
3. (abbreviation, alt-of, countable, uncountable)Abbreviation of diesel exhaust fluid.
4. (abbreviation, alt-of, countable, initialism, uncountable)Initialism of defence point.
5. (abbreviation, alt-of, countable, initialism, uncountable)Initialism of daily electronic feed.
6. (abbreviation, alt-of, countable, initialism, uncountable)Initialism of delayed electronic feed.

adv

1. (abbreviation, alt-of, clipping, slang)Clipping of definitely.

   “i can def sneak out tn. where should i meet u?”

   “And focus on cleaning the park. But we should def get waffle fries after.”

   “Not to toot our own horn, but we def had Austin Powers on VHS. This fun pop culture costume for couples may require some planning in advance to come up with these unique costumes, but trust us—it’ll pay off!”

   “While deets on her earnings aren't really public, we can def assume that Billie raked in a ton of dough from her Nike deal alone since each pair retails for a decent amount of $$$.”

adj

1. (slang)Excellent; very good.

   “You real def. I’m gonna put you on stage.”

   “See I do this thing, so come pursue this king / One minor rhyme is all you just bring / Cause I’m the best I’m def, ask the rest they left”

   “L.A.—The Second Deffest City of Hip-Hop [title]”

   “I’m a Flavor Unit MC / And that means I’m one of the roughest, def-est, toughest, best-est”