Hmm vs. Hum — What's the Difference?

Used to express reflection, uncertainty, or hesitation

To emit a continuous low droning sound like that of the speech sound (m) when prolonged.

Indicating thinking or pondering.

To emit the continuous droning sound of a bee on the wing; buzz.

A demand for an answer to a question.

To give forth a low continuous drone blended of many sounds

(intransitive) To make a thoughtful humming noise.

To be in a state of busy activity.

To produce a tune without opening the lips or forming words.

To sing (a tune) without opening the lips or forming words.

(Baseball) To throw or pitch (a ball) very fast.

The sound produced by humming.

The act of humming.

Used to indicate hesitation, surprise, or displeasure.

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.

(dated) An imposition or hoax; humbug.

(obsolete) 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.

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

(transitive) To express by humming.

(intransitive) To drone like certain insects naturally do in motion, or sounding similarly

(intransitive) To buzz, be busily active like a beehive

(intransitive) To produce low sounds which blend continuously

To reek, smell bad.

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

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

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

To make a low, prolonged sound, like that of a bee in flight; to drone; to murmur; to buzz; as, a top hums.

To make a nasal sound, like that of the letter m prolonged, without opening the mouth, or articulating; to mumble in monotonous undertone; to drone.

To make an inarticulate sound, like h'm, through the nose in the process of speaking, from embarrassment or a affectation; to hem.

To express satisfaction by a humming noise.

To have the sensation of a humming noise; as, my head hums, - a pathological condition.

To sing with shut mouth; to murmur without articulation; to mumble; as, to hum a tune.

To express satisfaction with by humming.

To flatter by approving; to cajole; to impose on; to humbug.

A low monotonous noise, as of bees in flight, of a swiftly revolving top, of a wheel, or the like; a drone; a buzz.

Any inarticulate and buzzing sound

A buzz or murmur, as of approbation.

An imposition or hoax.

An inarticulate nasal sound or murmur, like h'm, uttered by a speaker in pause from embarrassment, affectation, etc.

A kind of strong drink formerly used.

Ahem; hem; an inarticulate sound uttered in a pause of speech implying doubt and deliberation.

The state of being or appearing to be actively engaged in an activity;

An Islamic fundamentalist group in Pakistan that fought the Soviet Union in Afghanistan in the 1980s; now operates as a terrorist organization primarily in Kashmir and seeks Kashmir's accession by Pakistan

A humming noise;

Sing with closed lips;

Be noisy with activity;

Sound with a monotonous hum

Make a low continuous sound;