# boolean

/buˈɫiən/ (US) · CEFR C1 · Adjective

Source: https://englishreference.com/word/boolean
Updated: 2026-07-22

## Definition

describing a system of logic where there are only two possible values, usually 'true' or 'false'. You use this most often when talking about computers or math.

For teachers: relating to a system of symbolic logic or computer data that uses only two values, typically represented as 1 and 0, or true and false. Often used to describe search operators or programming variables.

## Examples

- The search uses boolean logic to find the right results.
- In computer programming, a boolean variable is used to track whether a specific condition has been met.
- The database query failed because the boolean operators were incorrectly nested, causing the system to return results that matched neither of the intended criteria.

## Usage notes

- Typically used attributively before a noun like 'logic', 'operator', or 'variable'.

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