What does ontology mean?
Ontology is a term with both philosophical and technical meanings. In philosophy, it names the study of being and existence: what kinds of entities exist, what relations they enter into, and what makes them real or intelligible. In computer science, linguistics, and information science, an ontology is a formal description of a domain, naming its important concepts and specifying how those concepts relate. The technical sense has become especially prominent as organizations seek to make large bodies of information consistent and machine-readable. The word is related to the Greek roots for “being” and “study,” and its modern philosophical sense developed from the Greek term ontologia. In ordinary conversation, “ontology” is uncommon and usually signals a discussion of fundamental questions or, in technical contexts, structured knowledge representation.
nounIn philosophy, ontology is the branch of metaphysics concerned with the nature of being and the fundamental categories of existence. In computer science and information science, it is a formal representation of a domain, including its entities, relationships, and constraints.
- The branch of philosophy that studies being, existence, and the fundamental structure of reality.
- In computer science and information science, a formal, organized representation of a subject domain, its entities, properties, and relationships.
- A theory or account of the basic kinds of entities and relations recognized in a domain.
"The conference brought together specialists in philosophy, linguistics, and computer science to discuss how an ontology can organize knowledge about a subject."
"Her paper examines ontology, asking whether properties such as beauty and usefulness are part of the objects that possess them."
"The developers built a domain ontology to connect information from several different databases."
The plural is used especially for distinct philosophical systems or formal models in different domains.
"The researchers compared ontologies representing medical, legal, and scientific concepts."
Ontology asks the most fundamental question in philosophy: what kinds of things exist, and what makes them the things they are?
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does ontology come from?
The word comes from Greek ontologia, formed from on or ontos, meaning “being” or “that which exists,” and -logia, meaning “study of.” The form entered English through philosophical usage, where it refers to the investigation of existence and being. The same underlying roots appear in related terms such as ontic, concerning what exists, and ontogenesis, referring to the origin or development of an organized being.
Related word forms
How ontology is actually used
In general use, the word is associated primarily with philosophy. In computing, it is a technical term for a structured model of knowledge and may sound formal or specialized. The plural is usually ontologies.
Easily confused with ontology
Ontology concerns what exists and the basic structure of reality, whereas epistemology concerns knowledge, its sources, and the grounds for justified belief.