ontology

noun

on·​tol·​o·​gy än-ˈtä-lə-jē 

1

: a branch of metaphysics concerned with the nature and relations of being

Ontology deals with abstract entities.

2

: a particular theory about the nature of being or the kinds of things that have existence

ontologist

än-ˈtä-lə-jist 

noun

Examples of ontology in a Sentence

Recent Examples on the Web

In my industry, healthcare, for example, an ontology might connect a member to a health plan, a service to a provider, a claim to a diagnosis and a diagnosis to a clinical condition. — Somnath Banerjee, Forbes.com, 14 Sep. 2026

Word History

Etymology

New Latin ontologia, from ont- + -logia -logy

First Known Use

1663, in the meaning defined at sense 1

Rhymes for ontology

• anthology
• apology
• astrology
• biology
• christology
• chronology
• conchology
• cosmology
• cryptology
• cytology
• doxology
• ecology