# ontology

/ɑnˈtɑɫədʒi/ (US) · /ɒntˈɒlədʒi/ (UK) · CEFR C2 · Noun

Source: https://englishreference.com/word/ontology
Updated: 2026-05-18

## Definition

a system of ideas that explains what things exist and how they are related. It is like a map of all the different types of things in the world and how they connect.

For teachers: a branch of metaphysics concerned with the nature of existence and the categories of being. In computer science, it refers to a formal representation of knowledge as a set of concepts within a domain and the relationships between those concepts.

## Examples

- The philosopher spent years developing a new ontology of the mind.
- The software uses a medical ontology to ensure that all patient records use the same standard terms for diagnoses.
- By establishing a shared ontology, the research team was able to integrate data from various sources, allowing the AI to recognize patterns that individual databases had previously missed.

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