perpetual motion

noun

Definition of perpetual motion

1 : the motion of an ideal mechanism that could continue to operate indefinitely without drawing upon an external source of energy

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Cite this Entry

“Perpetual motion.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/perpetual%20motion. Accessed 28 May. 2020.

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