equa·​tion | \ i-ˈkwā-zhən How to pronounce equation (audio) 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 But the chance to add Wagner to a defense that includes ascending second-year inside linebacker Ernest Jones changed the equation. Gary Kleinstaff Writer, Los Angeles Times, 4 Apr. 2022 Russia’s invasion of Ukraine dramatically changed the equation. Dominique Soguel, The Christian Science Monitor, 1 Apr. 2022 But the more transmissible omicron variant has changed the equation, and one by one the island nations have been succumbing to COVID-19. Nick Perry, ajc, 18 Mar. 2022 But Russia’s invasion of Ukraine has changed the equation. Amit Katwala, Wired, 2 Mar. 2022 But government incentives for electric cars, and penalties for carmakers that don’t meet emissions targets, have changed the equation. New York Times, 8 Feb. 2022 But the recent inflation surge has changed that equation and made rate increases more politically tolerable on both sides of the aisle. Nick Timiraos, WSJ, 14 Jan. 2022 Staying at home has limited his risk, and omicron hasn’t changed the equation. oregonlive, 8 Jan. 2022 Since the infrastructure bill was drafted, new variants emerged and changed the equation. Joe Crowley, Fortune, 15 Dec. 2021 See More

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.

First Known Use of equation

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

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Time Traveler for equation

Time Traveler

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

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Dictionary Entries Near equation

equate with/and



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Statistics for equation

Last Updated

15 May 2022

Cite this Entry

“Equation.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/equation. Accessed 19 May. 2022.

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More Definitions for equation


equa·​tion | \ i-ˈkwā-zhən How to pronounce equation (audio) \

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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