equation

noun

equa·​tion i-ˈkwā-zhən How to pronounce equation (audio)
also -shən
Synonyms of equationnext
1
a
: 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
To bring governmental enterprises and payment for them into immediate equation … —R. G. Tugwell
2
a
: 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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The Angels’ first series next week is against the Texas Rangers, who have artificial turf, so that could play a part in the equation. — Jeff Fletcher, Oc Register, 4 July 2026 What’s more, the Man himself — or, more specifically, the Sophia side of the equation — was a new level not just for the story, but for the writers as well. — Josh Wigler, HollywoodReporter, 6 July 2026 The price equation If OPEC turns the spigots to max, a complex operation with no guarantee of success, all that oil may have nowhere to go. — David Goldman, CNN Money, 6 July 2026 While most tidal effects were easily canceled out with the combination of data from the two satellites, one lunisolar tide called K1 brought uncertainty into the equation. — Mary Randolph, Scientific American, 8 July 2026 See All Example Sentences for equation

Word History

First Known Use

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

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

Phrases Containing equation

Rhymes for equation

See All Rhymes for equation

Browse Nearby Words

equate with/and
equation
equational
See all Nearby Words

Cite this Entry

“Equation.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/equation. Accessed 10 Jul. 2026.

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Kids Definition

equation

noun
equa·​tion i-ˈkwā-zhən How to pronounce equation (audio)
also -shən
1
: the act or process of equating : the state of being equated
2
a
: a statement of the equality of two mathematical expressions
b
: an expression involving chemical symbols for a chemical reaction

Medical Definition

equation

noun
equa·​tion
i-ˈkwā-zhən also -shən
: an expression representing a chemical reaction quantitatively by means of chemical symbols
Last Updated: - Updated example sentences
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