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- Latin · derived fromperpetuum
- English todayperpetuum mobile
From Latin perpetuum (neutral inflection of perpetuus “perpetual”) + Latin mōbile (neutrum of mōbilis “mobile, moving”), used together as a noun, thus literally meaning “perpetual mover”. Although often said to literally mean “perpetual motion”, the latter in Latin is mōtus perpetuus. A perpetuum mobile is a device that exhibits perpetual motion.
Etymology from Wiktionary, CC BY-SA 4.0.