\Hum\, v. i. [imp. & p. p. {Hummed}; p. pr. & vb. n.
{Humming}.] [Of imitative origin; cf. G. hummen, D. hommelen.
[root]15.]
1. To make a low, prolonged sound, like that of a bee in
   flight; to drone; to murmur; to buzz; as, a top hums. --P.
   Fletcher.
         Still humming on, their drowsy course they keep.
                                               --Pope.
2. 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.
         The cloudy messenger turns me his back, And hums.
                                               --Shak.
3. [Cf. {Hum}, interj.] To make an inarticulate sound, like
   h'm, through the nose in the process of speaking, from
   embarrassment or a affectation; to hem.
4. To express satisfaction by a humming noise.
         Here the spectators hummed.           --Trial of the
                                               Regicides.
Note: Formerly the habit of audiences was to express
      gratification by humming and displeasure by hissing.
5. To have the sensation of a humming noise; as, my head
   hums, -- a pathological condition.

\Hum\, v. t.
1. To sing with shut mouth; to murmur without articulation;
   to mumble; as, to hum a tune.
2. To express satisfaction with by humming.
3. To flatter by approving; to cajole; to impose on; to
   humbug. [Colloq. & Low]

\Hum\, n.
1. A low monotonous noise, as of bees in flight, of a swiftly
   revolving top, of a wheel, or the like; a drone; a buzz.
         The shard-borne beetle with his drowsy hums. --Shak.
2. Any inarticulate and buzzing sound; as:
   (a) The confused noise of a crowd or of machinery, etc.,
       heard at a distance; as, the hum of industry.
             But 'midst the crowd, the hum, the shock of men.
                                               --Byron.
   (b) A buzz or murmur, as of approbation. --Macaulay.
3. An imposition or hoax.
4. [Cf. {Hem}, interj.] An inarticulate nasal sound or
   murmur, like h'm, uttered by a speaker in pause from
   embarrassment, affectation, etc.
         THese shrugs, these hums and ha's.    --Shak.
5. [Perh. so called because strongly intoxicating.] A kind of
   strong drink formerly used. [Obs.] --Beau. & Fl.
{Venous hum}. See under {Venous}.

\Hum\, interj. [Cf. {Hem}, interj.]
Ahem; hem; an inarticulate sound uttered in a pause of speech
implying doubt and deliberation. --Pope.