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English definition of “hum”


verb     /hʌm/ (-mm-)
[I] to make a continuous low sound : The computers were humming in the background . What's that strange humming sound ?Sounds made by objects, movement or impact [I or T] to sing without opening your mouth : She hummed to herself as she walked to school . I've forgotten how that tune goes - could you hum it for me?Singing in general [I] informal to be busy and full of activity , excitement , sounds , or voices : The pub was really humming last night .Busy and activeHurrying and doing things quickly
(Definition of hum verb from the Cambridge Advanced Learner's Dictionary & Thesaurus © Cambridge University Press)
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