equa·​tion | \ i-ˈkwā-zhən also -shən \

Definition of equation

1a : the act or process of equating
b(1) : an element affecting a process : factor
(2) : a complex of variable factors
c : a state of being equated specifically : a state of close association or identification bring governmental enterprises and payment for them into immediate equation — R. G. Tugwell
2a : a usually formal statement of the equality or equivalence of mathematical or logical expressions
b : an expression representing a chemical reaction quantitatively by means of chemical symbols

Examples of equation in a Sentence

the equation of material wealth with happiness

Recent Examples on the Web

Once he is cleared for 11-on-11 drills that will obviously change the equation some. Mike Vorel, The Seattle Times, "Analysis: Impressions from day four of Seahawks training camp," 30 July 2018 But the Germans tied it up in the 48th minute off a goal from Reus, and Kroos's winner changes the equation entirely. Charlotte Carroll, SI.com, "Watch: Toni Kroos Gives Germany Win Over Sweden With Incredible Stoppage-Time Goal," 23 June 2018 So if adding more weight carrying capacity won’t work, maybe the answer lies on the other side of the equation—just carry less. David Hambling, Popular Mechanics, "The Overloaded Soldier: Why U.S. Infantry Now Carry More Weight Than Ever," 26 Dec. 2018 Where canal houses are concerned, both uniformity and individuality are part of the equation. Steve King, Condé Nast Traveler, "Why We Keep Going Back to Amsterdam," 24 Dec. 2018 For Furby collectors, however, profitability is not part of the equation. Kaitlyn Tiffany, Vox, "Every Furby gets a home," 21 Dec. 2018 Add a dance floor to the equation, and magic happens. Kayla Keegan, Good Housekeeping, "Camilla Parker Bowles Proves She's THE Queen of the Dance Floor in Hilarious New Clip," 8 Nov. 2018 Securing a software platform that serves 2.23 billion users is an extremely challenging task, and adding hardware to that equation just complicates existing concerns. Casey Newton, The Verge, "Google has a big advantage over Facebook in a crisis," 10 Oct. 2018 Add two kids and her own personal home renovation to the equation, and there aren't many hours left in the day. Taysha Murtaugh, Country Living, "Here's What Flip or Flop's Christina El Moussa Does Every Day to Stay in Such Great Shape," 13 Sep. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'equation.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of equation

14th century, in the meaning defined at sense 1a

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Last Updated

23 Jan 2019

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The first known use of equation was in the 14th century

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More Definitions for equation



English Language Learners Definition of equation

mathematics : a statement that two expressions are equal (such as 8 + 3 = 11 or 2x - 3 = 7)
: a complicated situation or issue
: the act of regarding two things as the same : the act of equating things


equa·​tion | \ i-ˈkwā-zhən \

Kids Definition of equation

1 : a statement of the equality of two mathematical expressions
2 : an expression representing a chemical reaction by means of chemical symbols


equa·​tion | \ i-ˈkwā-zhən also -shən\

Medical Definition of equation

: an expression representing a chemical reaction quantitatively by means of chemical symbols

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More from Merriam-Webster on equation

Rhyming Dictionary: Words that rhyme with equation

Spanish Central: Translation of equation

Nglish: Translation of equation for Spanish Speakers

Britannica English: Translation of equation for Arabic Speakers

Britannica.com: Encyclopedia article about equation

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