equation

American  

[ih-kway-zhuhn, -shuhn] / ɪˈkweɪ ʒən, -ʃən /

noun

• equations
  plural

1. the act of equating or making equal; equalization.

   the symbolic equation of darkness with death.

2. equally balanced state; equilibrium.

3. Mathematics. an expression or a proposition, often algebraic, asserting the equality of two quantities.

4. Also called chemical equation. Chemistry. a symbolic representation showing the kind and amount of the starting materials and products of a reaction.

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equation British  

/ ɪˈkweɪʒən, -ʃən /

noun

1. a mathematical statement that two expressions are equal: it is either an identity in which the variables can assume any value, or a conditional equation in which the variables have only certain values (roots)

2. the act of regarding as equal; equating

3. the act of making equal or balanced; equalization

4. a situation, esp one regarded as having a number of conflicting elements

   what you want doesn't come into the equation

5. the state of being equal, equivalent, or equally balanced

6. a situation or problem in which a number of factors need to be considered

7. See chemical equation

8. astronomy See personal equation

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equation Scientific  

/ ĭ-kwā′zhən /

1. Mathematics A written statement indicating the equality of two expressions. It consists of a sequence of symbols that is split into left and right sides joined by an equal sign. For example, 2 + 3 + 5 = 10 is an equation.

2. Chemistry A written representation of a chemical reaction, in which the symbols and amounts of the reactants are separated from those of the products by an equal sign, arrow, or a set of opposing arrows. For example, Ca(OH) ₂ + H ₂ SO ₄ = CaSO ₄ + 2H ₂ O, is an equation.

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Other Word Forms

Derived Forms

• nonequation
  noun
• equational
  adjective
• equationally
  adverb

Inflected Forms

Nouns

• equations
  plural

Etymology

Origin of equation

1350–1400; Middle English < Latin aequātiōn- (stem of aequātiō ) an equalizing. See equate, -ion

Explanation

In an equation, the quantities on both sides of the equal sign are equal. That's the mathematical meaning of equation, but equation can also be used in any number of situations, challenges, or efforts to solve a problem. The "equa" at the beginning of equation will be familiar from other words such as "equal," "equality," and "equate." All of these words have to do with making things balance out. An equation is a statement of the equality of two quantities. If that equation is not a mathematical one but rather, say, an interpersonal one, it's still a situation in which you might try to make the two sides equal. For example, taking marriage out of the equation might make it easier for two people to decide to stay together for a while.

Example Sentences

See Examples For:

equation equations

But a low mortgage rate is only one part of the equation.

From MarketWatch ● Sep. 29, 2026

It seems like a simple equation: $338 million produces 100.

From Los Angeles Times ● Sep. 28, 2026

Again, experience will come into the equation if Cox's form suggests a more drastic decision must be made.

From BBC ● Sep. 28, 2026

This is possible because mass and energy are related through Einstein's famous equation E=mc2.

From Science Daily ● Sep. 26, 2026

Somehow I did not figure us—the horse and me—into the equation.

From This Side of Wild by Gary Paulsen

This fairly straightforward method is also used by computer programs in nearly every field to solve far larger systems of equations.

From The Wall Street Journal ● Oct. 8, 2026

Fightstarters over ambiguous issues — the annual argument over “Baby, It’s Cold Outside,” the internet-breaking Dress, countless poorly written math equations on Facebook — are evergreen.

From Salon ● Sep. 23, 2026

It concerns the equations describing how fluids such as air and water move, which are used in aircraft design, weather forecasting and the study of blood flow.

From Barron's ● Sep. 8, 2026

The problem was part of the Navier-Stokes equations, external, which concern how fluids move.

From BBC ● Sep. 8, 2026

Natural laws are described with equations, and equations, in a sense, are simply tools where you plug in numbers and get another number out.

From "Zero: The Biography of a Dangerous Idea" by Charles Seife