noun
treadwheel; treadmill
Historical term for a human-powered wheel used to pump water or perform other work, often in agricultural settings.
江戸時代の農民は踏み車で田んぼに水を引いた。
Farmers in the Edo period used treadwheels to draw water into the rice paddies.
Compound of 踏み (fumi, 'stepping') + 車 (kuruma, 'wheel'). The exact historical derivation is uncertain, but the term transparently describes a wheel turned by stepping.