“energy equation”

We have one entry that includes the term energy equation.

mass-energy equation

noun

: an equation for the interconversion of mass and energy: E = MC2 where E is energy in ergs, M is mass in grams, and C is the velocity of light in centimeters per second compare conservation of energy, conservation of mass

See the full definition

Word of the Day

Listen to the pronunciation of abhor

See Definitions and Examples »

Test Your Vocabulary

Commonly Misspelled Words Vol. 2 Quiz

  • sequel spelled three ways with the incorrect ways crossed out and the correct spelling circled
  • Rachel seemed to be _____ in every endeavor she started.
True or False

Test your knowledge - and maybe learn something along the way.

TAKE THE QUIZ
Play Blossom: Solve today's spelling word game by finding as many words as you can using just 7 letters. Longer words score more points.

Pick the best words!

PLAY
Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!

Games & Quizzes

See All
Play Quordle: Guess all four words in a limited number of tries. Each of your guesses must be a real 5-letter word.
Quordle Can you solve 4 words at once?
Play Blossom: Solve today's spelling word game by finding as many words as you can using just 7 letters. Longer words score more points.
Blossom Word Game Pick the best words!
Play Missing Letter: a crossword with a twist. Each of the 25 puzzle words start with a different letter of the alphabet. Which letter is missing?
Missing Letter A crossword with a twist
winning words from the national spelling bee logo
Spelling Bee Quiz Can you outdo past winners of the National Spelli...