relativistic mass

noun Physics.

the mass of a body in motion relative to the observer: it is equal to the rest mass multiplied by a factor that is greater than 1 and that increases as the magnitude of the velocity increases.

Nearby words

  1. relatively prime numbers,
  2. relativeness,
  3. relativism,
  4. relativist,
  5. relativistic,
  6. relativistic quantum mechanics,
  7. relativity,
  8. relativize,
  9. relator,
  10. relatum Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Science definitions for relativistic mass

relativistic mass


In Special and General Relativity, the observed mass of an object moving with respect to the observer. The relativistic mass is a function of the rest mass and the velocity of the object. Compare rest mass.
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