ENGLISH
REFERENCE

def

adv. degree
B2 Upper Intermediate def Slang

adv. short for 'definitely'. You use it when you are 100% sure about something or agree completely. It is very casual and common in text messages.

adv. a clipped form of 'definitely' used to express absolute certainty or agreement. Highly informal and primarily found in digital communication or casual speech.


SIMPLE

I'm def coming to the party tonight.

CONTEXTUAL

We should def grab lunch next week once our exams are finally over.

COMPLEX

While formal writing requires the full adverb, in rapid digital exchanges, users def prefer shorter forms to maintain the conversational pace.

Origin

Clipping of definitive or definitely; alternatively an eye spelling of death referring to an absolute.

Usage

Typically placed before the main verb or adjective it modifies; restricted to informal registers.

Pitfall

This is def a good idea for the report.This is definitely a good idea for the report.'Def' is slang and should not be used in formal or professional writing.

© 2026 English Reference