What does hum mean?
To hum is to make a low, continuous sound with the voice, usually by vibrating the lips while keeping them closed. People hum to express contentment, fill a silence with music, or accompany themselves while working or travelling. The same verb can mean singing a tune without words, and a hum may also refer to the steady sound produced by machinery or the background noise of a busy place. Figuratively, the word suggests a pleasant sense of satisfaction: someone who is happy may be said to be humming with pleasure. A hum is also a quiet, continuous sound rather than a single note or loud vocal expression. The word is common in both British and American English and is used in everyday speech as well as in descriptions of technology, crowds, workplaces, and music.
To make a low, continuous sound with the voice, usually with the lips closed; to sing without words.
"The baby hummed contentedly as she rocked to sleep."
Figuratively, it can mean to be visibly pleased or satisfied.
A low, continuous sound, especially one made by a person humming, a machine, or a crowd.
"A hum of conversation rose from the crowded café."
In figurative use, it can refer to a widespread feeling or atmosphere, such as a hum of excitement.
Used for distinct low continuous sounds, especially sounds produced by machines, crowds, or groups.
"The distant hums of traffic drifted through the open window."
Humming is one of the few musical actions that requires no words: a single steady breath can carry a whole melody.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does hum come from?
The verb 'hum' is an imitative word: its sound was formed to suggest the low, steady noise made by a person humming. The noun developed from this verb and came to mean both the act of humming and the sound produced by humming. The word has been used in English since the early modern period and is not a borrowing from another clearly identifiable language. Its later figurative meanings developed from the association between humming and contentment.
Related word forms
How hum is actually used
The word is neutral in general usage. As a verb, it commonly describes making a tune with closed lips; figuratively, 'hum' can imply being deeply pleased or satisfied, as in 'humming with pride.' As a noun, a 'hum of activity' refers to widespread movement or conversation.