from The American Heritage® Dictionary of the English Language, 5th Edition.

  • noun One regarded as the initial source of energy directed toward a goal.
  • noun The initial force, such as electricity, wind, or gravity, that engages or moves a machine.
  • noun A machine or mechanism that converts natural energy into work.
  • noun Any of various heavy-duty trucks or tractors.
  • noun Philosophy In Aristotelian philosophy, the self-moved being that causes all motion.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

  • noun philosophy The initial agent that is the cause of all things.
  • noun A machine, such as a water wheel or steam engine, that receives and modifies energy as supplied by some natural source or fuel and transforms it into mechanical work
  • noun automotive The front part of a semi-trailer type truck, i.e., the tractor to which the trailer part attaches.
  • noun US A military or heavy construction vehicle.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

  • noun an agent that is the cause of all things but does not itself have a cause


from Wiktionary, Creative Commons Attribution/Share-Alike License

Originally in translation of Latin primum mobile.


Help support Wordnik (and make this page ad-free) by adopting the word prime mover.


    Sorry, no example sentences found.


Log in or sign up to get involved in the conversation. It's quick and easy.