What is the meaning of Hum?

A hummed tune, i.e. created orally with lips closed.

An often indistinct sound resembling human humming.

Busy activity, like the buzz of a beehive.

Unpleasant odour.

An imposition or hoax; humbug.

A kind of strong drink.

A phenomenon, or collection of phenomena, involving widespread reports of a persistent and invasive low-frequency humming, rumbling, or droning noise not audible to all people.

To make a sound from the vocal cords without pronouncing any real words, with one's lips closed.

To express by humming.

To drone like certain insects naturally do in motion, or sounding similarly.

To buzz, be busily active like a beehive

To produce low sounds which blend continuously

To reek, smell bad.

To flatter by approving; to cajole; to deceive or impose upon; to humbug.

Synonym of hmm: a noise indicating thought, consideration, &c.

Synonym of um: a noise indicating doubt, uncertainty, &c.

rough sea

to bathe

paper

Alternative form of hem (them)

water

also, as well as

(good) mood

uttering to attract attention, without literal meaning

um..., hm

Archaic spelling of um.

Obsolete spelling of um.

hmm

hillock

barrow, tumulus (mound of earth raised over a grave)

arrogance

Source: wiktionary.org