To buzz, be busily active like a beehive
To produce low sounds which blend continuously
To express by humming.
To reek, smell bad.
To make a sound from the vocal chords without pronouncing any real words, with one's lips closed.
To drone like certain insects naturally do in motion, or sounding similarly
Unpleasant odour.
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.
Busy activity, like the buzz of a beehive.
A hummed tune, i.e. created orally with lips closed.
An often indistinct sound resembling human humming.
Synonym of um: a noise indicating doubt, uncertainty, &c.
Synonym of hmm: a noise indicating thought, consideration, &c.
To engage in some activity with vigor.
To crash into something.
To invest a resource (money, material, energy) into something.