1. A humming noise
   - hum 
2. The act of singing with closed lips

1. Sing with closed lips
   "She hummed a melody" 
2. Be noisy with activity
   - buzz, seethe 
3. Sound with a monotonous hum
   - thrum 
4. Make a low continuous sound
   "The refrigerator is humming"

Derived forms: hummings

See also: hummer

Type of: be, go, make noise, noise, resound, sing, singing, sound, vocalising [Brit], vocalizing

Encyclopedia: Hum Hum, Croatia

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