# flywheel

Pronunciation: say "FLY-weel" US /ˈflaɪˌwil/, UK /ˈflaɪˌwiːl/

## Noun

1. A heavy rotating mass that keeps a machine's speed within set limits as it gains or releases energy unevenly, or that holds energy for later use.
   - Simple: A heavy spinning wheel that helps a machine keep a steady speed and can store energy.
   - _Mechanics replaced the cracked flywheel before the motor would run evenly again._
   - _Some buses recover braking energy by spinning up a flywheel and drawing on it later._

## Origin

Formed by combining "fly" and "wheel."

Source: DictionaryAI, https://dictionaryai.com/define/flywheel (written from Wiktionary data, CC BY-SA 4.0: https://creativecommons.org/licenses/by-sa/4.0/).