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English definition of “hum”


verb [I/T]    /hʌm/ (-mm-)
to make a continuous , low sound , or to sing a tune with closed lips : [I] Debbie always hums to herself when she listens to music . [T] I’ve forgotten how that tune goes – could you hum it for me? fig. If something is humming, it is very busy and full of activity : [I] Factories that make paper products are humming at 97% of capacity .
(Definition of hum verb from the Cambridge Academic Content Dictionary © Cambridge University Press)
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