noun / verb
whir
WUR/wɜːr/
A continuous soft buzzing sound, or to make this sound.
The desk fan whirs softly as its blades spin steadily.

Etymology
Whirren described flying or darting with a whizzing sound. The selected meaning focuses on the sound itself: a sustained buzz or hum rather than the rushing movement.
More examples
- A faint whir comes from the refrigerator.
- The sewing machine whirred as she stitched the curtain.
- The laptop's whir grows louder when it gets hot.
Forms
whir · whirs · whirred · whirring