Cambridge Dictionaries online Cambridge Dictionaries online

The most popular online dictionary and thesaurus for learners of English

English definition of “REM”

REM

noun [U] uk   /rem/ /ˌɑːr.iːˈem/
abbreviation for rapid eye movement: quick movements of the eyes that happen at certain times while you are sleeping and dreaming: REM sleep
(Definition of REM from the Cambridge Advanced Learners Dictionary & Thesaurus © Cambridge University Press)
What is the pronunciation of REM?
Add Cambridge dictionaries to your browser to your website

Word of the Day

stampede

When animals or people stampede, they all move quickly in the same direction, often because they are frightened.

Word of the Day

Blog

Read our blog about how the English language behaves.

Learn More

New Words

Find words and meanings that have just started to be used in English, and let us know what you think of them.

Learn More