- the energy equivalent to the mass of a particle at rest in an inertial frame of reference, equal to the rest mass times the square of the speed of light.
Origin of rest energy
First recorded in 1935–40
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
- In Special Relativity, the energy corresponding to the rest mass of a body, equal to the rest mass multiplied by the speed of light squared. See more at mass-energy equivalence.
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