primum mobile

pri·​mum mo·​bi·​le | \ ˈprī-məm-ˈmō-bə-lē How to pronounce primum mobile (audio) , ˈprē- \
plural primum mobiles

Definition of primum mobile

: the outermost concentric sphere conceived in medieval astronomy as carrying the spheres of the fixed stars and the planets in its daily revolution

First Known Use of primum mobile

15th century, in the meaning defined above

History and Etymology for primum mobile

Middle English, borrowed from Medieval Latin prīmum mōbile, literally, "first moving thing" (as translation of Arabic al-muḥarrik al-awwal) from Latin prīmum, neuter of prīmus "first, earliest" + Medieval Latin mōbile, noun derivative from neuter of Latin mōbilis "moving quickly, shifting" — more at prime entry 2, mobile entry 1

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The first known use of primum mobile was in the 15th century

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Cite this Entry

“Primum mobile.” Dictionary, Merriam-Webster, Accessed 17 Jan. 2021.

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