equation

American  

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

noun

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

• equationally
  adverb
• nonequation
  noun
• equational
  adjective

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

In truth, it is a mess on both sides of the equation.

From BBC • May 29, 2026

“Bluntly, we have not had the right fashion and value equation for that category,” said Gap CEO Richard Dickson.

From MarketWatch • May 29, 2026

As soon as I came up with that little weird math equation, things started locking into place.

From Los Angeles Times • May 28, 2026

The people mover, once operational, is only one part of the equation.

From Barron's • May 27, 2026

Beside the fifth: You forgot to balance the equation.

From "The Sea in Winter" by Christine Day