Ontology
noun /ɒnˈtɒl.ə.dʒi/ — The philosophical study of being and existence
Definition
The branch of metaphysics that concerns itself with the nature of being and existence — what kinds of things exist, and what it means to exist at all.
Beyond the definition
The deepest possible question. Ontology asks not 'what is this?' but 'what does it mean for anything to be at all?'
Origin & history
From Greek 'ontos' (being, existence), genitive of 'einai' (to be) + 'logia' (study). Coined in the 17th century to name a discipline philosophy had always practiced.
Example sentences
Illustrative sentences for learning, not verified community posts or sourced quotations.
The novel raised ontological questions: was the narrator real within the story's own logic?
His ontology was materialist — he believed that only physical things truly existed.
Once you start asking ontological questions, everything else becomes temporarily less urgent.
How to use it
This entry uses a noun. Follow the examples for articles and singular or plural forms; not every noun takes “a” or “an.”
Choose “Ontology” when the meaning fits your context: The branch of metaphysics that concerns itself with the nature of being and existence — what kinds of things exist, and what it means to exist at all.
Synonyms
metaphysics, philosophy of being, existence theory
Related words
Ontology vs metaphysics
Ontology is a specific branch within the broader field of metaphysics. Metaphysics encompasses all study of ultimate reality, including time, space, causality, and existence.
Word in the Wild
Illustrative story: an imagined scene, not a documented event or interview.
At 4am, slightly ill and unable to sleep, he found himself staring at the ceiling with a question he couldn't stop turning over: what does it actually mean for something to exist?
Not as a thought experiment. As a genuine, slightly vertiginous question. Was his body a collection of cells, or something those cells added up to, or something else entirely that the cells were just expressing?
He lay there until 6am and didn't resolve the question. He got up and made coffee and felt, somehow, better than he had at midnight — as though the question itself, held seriously in the dark, had done something useful.
Questions about this word
What does "Ontology" mean?
Ontology is noun meaning: The philosophical study of being and existence. The branch of metaphysics that concerns itself with the nature of being and existence — what kinds of things exist, and what it means to exist at all.
Which words express “questioning how we know things”?
Ontology — The philosophical study of being and existence
Where does the word "Ontology" come from?
From Greek 'ontos' (being, existence), genitive of 'einai' (to be) + 'logia' (study). Coined in the 17th century to name a discipline philosophy had always practiced.