def

adjective1

1. •
   (slang) Excellent; very good.

   • You real def. I’m gonna put you on stage. — 1985

adverb1

1. •
   (slang) Clipping of definitely.

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

noun2

1. •
   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.” — 1903
2. •
   Abbreviation of deficit.

noun1

1. •
   Abbreviation of definition.

   • Lots of writers, though, think fervent is synonymous with fervid, and most dictionary defs. don't do much to disabuse them. — 2004

noun4

1. •
   Abbreviation of diesel exhaust fluid.
2. •
   Initialism of defence point.
3. •
   Initialism of daily electronic feed.
4. •
   Initialism of delayed electronic feed.

noun1

1. •
   Abbreviation of defense.