hum

Everyday

1. To sing a tune with your lips closed, making a long «mmm» sound. tree →
2. To make a low, steady buzzing sound, like bees or a fridge. tree →
3. (noun) A low, continuous sound: «the hum of traffic». tree →
4. To be busy and lively: «The classroom was humming with activity». tree →

In the lessons

In music lessons children hum a tune before singing the words. In science, a hum is a sound made by vibrations, like insect wings or electrical machines. In stories it sets a scene: «the hum of bees in the garden», «the fridge hummed». Phrase: «hum along».

Examples

• She hummed a happy song while she painted. tree →
• Bees hum as they fly from flower to flower. tree →
• I could hear the hum of the fridge in the quiet kitchen. tree →
• Hum the tune if you forget the words. tree →
• The computer makes a soft hum. tree →
• The market was humming with people. tree →
• The hummingbird got its name from the hum of its wings. tree →
• The noisy hum of voices was hushed. tree →

Note

Spelling: double «m» before «-ed» and «-ing»: hummed, humming. A «hummingbird» beats its wings so fast that they hum. You hum with your mouth closed; you whistle with your lips open in a small «o».