1. The act of singing with closed lips
   "His constant humming of the tune became annoying"
    
2. A humming noise
   "the humming of distant traffic";
   - hum

1. Make a low continuous sound
   "The refrigerator is humming"
    
2. Sing with closed lips
   "She hummed a melody"
    
3. Sound with a monotonous hum
   "The air conditioner hummed all night";
   - thrum
    
4. Be noisy with activity
   "This office is humming with activity";
   - buzz, seethe
    
5. [Brit, informal] Smell badly and offensively
   "The garbage was humming in the summer heat";
   - reek, stink

Derived forms: hummings

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

Encyclopedia: Humming