a humming noise; "the hum of distant traffic" पर्याय: humming,
the state of being or appearing to be actively engaged in an activity; "they manifested all the busyness of a pack of beavers"; "there is a constant hum of military preparation" पर्याय: busyness,
sing with closed lips; "She hummed a melody"
make a low continuous sound; "The refrigerator is humming"