Cambridge Dictionaries online Cambridge Dictionaries online

The most popular online dictionary and thesaurus for learners of English

English definition of “on”

on

adverb (OPERATING)    /ɒn/ US  /ɑːn/
B2 used to show when something is operating or starting to operate: Could you switch on the radio? Would you turn the TV on? You left the bedroom light on.On or offFunctioningPerforming a function Grammar:On, ontoOn and onto are prepositions.See more
(Definition of on adverb (OPERATING) from the Cambridge Advanced Learner's Dictionary & Thesaurus © Cambridge University Press)
Focus on the pronunciation of on

Definitions of “on” in other dictionaries

Word of the Day

neighbourly

friendly or helpful

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