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English definition of “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)
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