prime mover

noun

1

a

: an initial source of motive power (such as a windmill, waterwheel, turbine, or internal combustion engine) designed to receive and modify force and motion as supplied by some natural source and apply them to drive machinery

b

: a powerful tractor or truck usually with all-wheel drive

2

: the self-moved being that is the source of all motion

3

: the original or most effective force in an undertaking or work

education is … a prime mover of cultural and societal change

—R. C. Buck

Examples of prime mover in a Sentence

She was the prime mover behind the town's annual summer festival.

Recent Examples on the Web

The contract with Fortescue—XCMG’s largest order outside of China for mining equipment—covers battery electric wheel loaders, wheel dozers, water carts, float prime movers and graders. —Ian Sayson, Forbes, 27 Nov. 2024

But there were significant changes below, with Brigham Young as the prime mover. —Jon Wilner, The Mercury News, 19 Nov. 2024

Yet that is an odd complaint for Washington to make, since at the WTO’s creation, in 1995, the United States was the prime mover behind the dispute settlement system and insisted on stronger rules and tougher enforcement mechanisms than in the previous General Agreement on Tariffs and Trade. —Douglas A. Irwin, Foreign Affairs, 6 Nov. 2018

The prime mover within the organization — the largest user — was the U.S. signatory, the Communications Satellite Corporation, or Comsat. —Neal B. Freeman, National Review, 17 Sep. 2024

Word History

Etymology

(sense 2) translation of Medieval Latin prīmum mōbile, prīmus mōtus, prīmus mōtor or other variants

Note: See also etymology at primum mobile.

First Known Use

1795, in the meaning defined at sense 1a

Medical Definition

prime mover

noun

ˈprīm-ˈmü-vər 

: agonist sense 1