Word.ws English Dictionary

E=mc²

UK/ˈiː ˌiːkwəlz ɛm siː ˈskwɛːd//ˈi ˌikwəlz ɛm si ˈskwɛɹd/

E=mc² noun: a formulation or realization that captures a profound thought in simple terms.

e=mc²: a formulation or realization that captures a profound thought in simple terms
Image: Stefan K-50678, CC BY-SA 3.0, via Wikimedia Commons

Noun

E=mc² (uncountable)

  1. (idiomatic, informal) A formulation or realization that captures a profound thought in simple terms.
    • "Beauty isn't about looking young." OK, so it's not E=mc² or even [Isaac] Newton's apple. But coming as it does from a top cosmetics company, it does represent an attitude readjustment that makes Saul's change of heart on the road to Damascus look like a passing fancy.1999, Mary Lynn Damhorst, Kimberly A. Miller-Spillman, Susan O. Michelman, The Meanings of Dress, New York, N.Y.: Fairchild Publications, →ISBN, page 351
    • What counted most through the generations, far more than any other factor, regardless of our race, was how we treated those we loved and how well we loved. That seemed the transcendent lesson or moral that my search had revealed. And it held true whether the figure was my mother or Fredda on one...2001, Neil Henry, “Tenth Man Classic”, in Pearl’s Secret: A Black Man’s Search for His White Family (The George Gund Foundation Imprint in African American Studies), Berkeley; Los Angeles, Calif....
  2. Used other than figuratively or idiomatically: E = mc²: energy equals mass times the speed of light squared.

Origin of E=mc²

After the formula of mass–energy equivalence, an important principle discovered by the German-born theoretical physicist Albert Einstein (1879–1955). The formula entered the popular consciousness after it was included in the opening pages of the Smyth Report (1945), a widely read document that explained the United States’ nuclear weapons program to the public for the first time. Its appearance alongside a portrait of the (already well known) Einstein on a Time magazine cover the following year consolidated its fame.

Words that rhyme with E=mc²

13 more rhymesFewer rhymes

Questions about E=mc²

What does E=mc² mean?
E=mc² means a formulation or realization that captures a profound thought in simple terms.
What part of speech is E=mc²?
E=mc² is a noun.
How do you pronounce E=mc²?
E=mc² is pronounced /ˈiː ˌiːkwəlz ɛm siː ˈskwɛːd/ (UK).

Words near E=mc² in the dictionary

  1. E5
  2. e6
  3. E85
  4. E85s
  5. E911
  6. E=mc²
  7. ea
  8. ea.
  9. EAA
  10. EaaS
  11. EAB

Source and license

Adapted from Wiktionary: E=mc² (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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Pronunciation audio from Wikimedia Commons, each file under its own free license: En-us-E%3Dmc2.ogg.

Cite this entry: “E=mc².” Word.ws, https://word.ws/e%3Dmc%C2%B2. Based on Wiktionary, CC BY-SA 4.0.