def

adj. · n.

def

1 excellent (adj.)
C1 Advanced Slang Archaic

a slang word for something that is very good or cool.

an adjective used to denote excellence or high quality; primarily associated with early hip-hop culture.

Example

That new song has a def beat.

Example

The DJ played a def set that kept the crowd dancing until the early hours of the morning.

Teacher's tip

This sense is largely dated and associated with 1980s hip-hop; modern learners will rarely hear it used by younger speakers.
- bad
- terrible
2 definition (n.)
B2 Upper Intermediate

a short way to write the word 'definition'.

a standard abbreviation for 'definition', frequently used in dictionaries, glossaries, and programming.

Example

Check the def of that word in the back of the book.

Example

The technical manual provides a clear def for every acronym used in the text.

Usage

Usually written rather than spoken; often followed by a period in formal documents.
- meaning
- explanation

Origin

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

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