verb, noun
verb (-mm-)
1 to sing a tune with your lips closed:
[V] She was humming softly to herself. * He began to hum along with the music. * [VN] What's that tune you're humming?
2 [V] to make a low continuous sound:
The computers were humming away. * The overhead wires hummed with power.
3 [V] (informal) to be full of activity:
The streets were beginning to hum with life. * The whole room was humming now. * Things were beginning to hum.
IDIOMS
hum and haw (BrE) (AmE hem and haw) (informal) to take a long time to make a decision or before you say sth:
We hummed and hawed for weeks before deciding to buy the house.
noun [sing.] ~ (of sth) a low continuous sound:
the hum of bees / traffic / voices * The room filled with the hum of conversation.
