rest mass

noun

Definition of rest mass

: the mass of a body exclusive of additional mass the body acquires by its motion according to the theory of relativity

First Known Use of rest mass

1914, in the meaning defined above

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The first known use of rest mass was in 1914

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Cite this Entry

“Rest mass.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/rest%20mass. Accessed 4 Aug. 2020.

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