waterwheel
/ˈwɔtərˌwil/
noun
- A large wheel that turns when water flows over or under it, used to power machinery.
- Farmers in the 19th century often relied on a waterwheel to run their sawmills.
- The museum has a working waterwheel that demonstrates how early factories got their power.
- The old mill used a waterwheel to grind grain into flour.