millwheel
mill‧wheel /ˈmɪlwiːl/
noun [countable] especially British English
a large wheel that is turned by water flowing past it to provide power to the machinery in a watermill
mill‧wheel /ˈmɪlwiːl/
noun [countable] especially British Englisha large wheel that is turned by water flowing past it to provide power to the machinery in a watermill