1. a continuous low sound

1. very busy or active
Usage: informal

1. making a continuous low sound
Usage: present participle of hum
2. singing with closed lips
Usage: present participle of hum

Examples

• The bees were humming around the flowers.
• She was humming her favorite song while cooking.
• The humming of the air conditioner kept me awake.
• The office was humming with activity before the deadline.
• I could hear him humming in the shower.
• The humming sound came from the refrigerator.
• The factory floor was humming with workers.