# singleton

/ˈsɪŋɡəɫtən/ (US) · /sˈɪŋɡəltən/ (UK) · CEFR C1 · Noun

Source: https://englishreference.com/word/singleton
Updated: 2026-08-15

## Definition

a single person or thing that is not part of a pair or a group. In computer science, it is also a design pattern where only one instance of an object can exist.

For teachers: an individual item or person that is distinct from a set, pair, or group. In software engineering, refers to a design pattern that restricts the instantiation of a class to one object.

## Examples

- The database uses a singleton to manage all connections.
- The teacher noticed a singleton sitting apart from the other students during the group activity.
- Implementing the logger as a singleton ensures that every module in the application writes to the same file without creating conflicting file handles or redundant memory allocations.

## Usage notes

- Commonly used in technical contexts like mathematics, statistics, and software development; in social contexts, it is a neutral term for an unmarried person.

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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.