# equation

/ɪˈkweɪʒən/ (US) · /ɪkwˈeɪʒən/ (UK)

Source: https://englishreference.com/word/equation
Updated: 2026-06-19

## Senses

### 1. mathematics

noun · CEFR B1

a mathematical statement that shows two amounts are equal using an equals sign (=).

For teachers: a formal statement of equality between two mathematical expressions, typically containing one or more variables.

- The students spent the afternoon solving a difficult algebra equation.
- The physicist derived a complex differential equation to model the fluid dynamics of the cooling system.

Usage: Countable; often used with the verbs 'solve', 'balance', or 'derive'.

### 2. balancing factors

noun · CEFR B2

a situation where you must consider several different things to find a solution or understand a problem.

For teachers: a complex situation or set of variables that must be balanced or considered as a whole.

- Money is only one part of the equation when you are choosing a new job.
- When planning urban expansion, environmental preservation must remain a central part of the equation.

Usage: Often used in the phrase 'part of the equation'.

### 3. equating things

noun · CEFR C1 · Academic

the act of treating two different things as if they are the same.

For teachers: the process of equating two or more elements or the state of being equal.

- The equation of wealth with happiness is a common mistake in modern society.
- The author's simplistic equation of political dissent with treason was widely criticised by civil rights advocates.

### 4. astronomical correction

noun · CEFR C2 · Technical

a small change made to a measurement to fix a regular error.

For teachers: a small correction applied to observed values to compensate for systematic errors or variations.

- The scientist applied a time equation to the data to get a more accurate result.
- The equation of time accounts for the discrepancy between apparent solar time and mean solar time throughout the calendar year.

## Examples

- The teacher wrote a simple math equation on the board.
- To solve for the unknown variable, you must balance both sides of the equation by performing the same operation on each.
- In physics, Einstein's famous equation describes the fundamental relationship between mass and energy, proving that they are essentially different forms of the same thing.

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From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.