Word.ws English Dictionary

mass-energy

mass-energy noun: mass and energy as a unified concept.

Noun

mass-energy (countable and uncountable, plural mass-energies)

  1. Mass and energy as a unified concept.
    • Whereas in classical physics mass and energy are distinct concepts, on relativistic scales, they become indistinguishable and are replaced by mass-energy.
    • In higher-energy physics, mass and energy eventually become meaningless as individual concepts; a particle's so-called "mass" is actually mass-energy and is often given equivalently in units of either mass (GeV/c²) or energy (GeV).
  2. (also spelled mass energy) The energy associated with any given mass according to special relativity, E = mc².

Adjective

mass-energy (not comparable)

  1. mass-to-energy
    • Mass-energy conversion occurs during nuclear fusion and fission.

Forms of mass-energy

pluralmass-energies

Questions about mass-energy

What does mass-energy mean?
Mass-energy means mass and energy as a unified concept.
What part of speech is mass-energy?
Mass-energy can be a noun or an adjective.
What is the plural of mass-energy?
The plural of mass-energy is mass-energies.

Words near mass-energy in the dictionary

  1. mass-applied
  2. mass-applies
  3. mass-apply
  4. mass-applying
  5. mass-energies
  6. mass-energy
  7. mass-market
  8. mass-produce
  9. mass-produced
  10. mass-produces
  11. mass-producing

Source and license

Adapted from Wiktionary: mass-energy (page history and authors). Text available under the Creative Commons Attribution-ShareAlike 4.0 license. Word.ws reformatted the entry and added links. Wiktionary data of 2026-09-02.

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Cite this entry: “mass-energy.” Word.ws, https://word.ws/mass-energy. Based on Wiktionary, CC BY-SA 4.0.