Primum mobile

Noun

Definitions

1.NounThe outermost celestial sphere of the heavens in Ptolemaic astronomy, which was believed to cause all the inner spheres to rotate.

2.NounThe prime mover or first cause (“an initial cause from which all other causes and effects follow”).

3.NounThe person or thing that is the main impetus for some action; a driving force.

The Daily Word NerdA new word, a puzzle, and a fun fact — free in your inbox every morning.

Free forever · unsubscribe anytime · all 14 newsletters

That email did not go through — please check it and try again.