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Lexicon.

ontology

noun [ɑnˈtɑlədʒi]
pronunciation CMU Pronouncing Dictionary, open source

Ontology means the science of being: in metaphysics the inquiry into what exists, what essential properties beings have, and what principles of being may be stated.

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Definitions

  1. philos. A department of metaphysics concerned with being as such: the nature, essential properties and relations of beings, or the principles and causes of being, beyond a mere report of a single sensory appearance.
    source Editorial team (in-house source, no external address)
  2. philos. / hist. lex. In a wider historical-lexical register: the science of being as a part of metaphysics; sometimes identified with metaphysics proper, that is with inference from known manifestations to an unknown being.
    source Editorial team (in-house source, no external address)
  3. philos. In a typology of schools: a body of claims about what exists (categories, substances, relations, modalities), apart from how we come to know appearances. A didactic contrast with phenomenology as a register of what shows up, without a leap into theses about an essence outside the appearance.
    source Editorial team (in-house source, no external address)
  4. comput. / tech. colloq. In computing and knowledge engineering (contemporary register): a formal description of concepts, types and relations in a given domain (e.g. a domain ontology in a knowledge base). A technical sense, without historical continuity with classical metaphysics; to confirm with a source at review.
    source Editorial team (in-house source, no external address)

Examples

Usage

Everyday English often treats ontology as a tag for "a general theory of reality" or "a list of what we take to exist", sometimes without separating philosophical, historical-lexical and computing registers. Precise prose marks the layers: a department of metaphysics about being (Webster, Skeat, Arct); a contrast with phenomenology (description of appearances); and contemporary jargon for formal concept models. Name the layer you intend. Otherwise the lemma melts into metaphysics alone, into ontologist as "adherent of metaphysics", and into ontology as a schema file in a knowledge base.

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Webster 1913 under Ontology gives Greek etymology with -logy (cf. F. ontologie) and sets the lemma inside metaphysics: inquiry into beings in themselves, or into principles and causes of being. Nearby: Ontologist, Ontological, Ontologic. Under Metaphysics it equates ontology with the science of real being as against phenomenal being, citing Hamilton (ontology, or metaphysics proper). Skeat 1910 has ONTOLOGY as the science of being, Bailey 1725 on beings in the abstract, and the Greek split from εἶναι plus -λογία. Facts come from those open lemmas; wording here is separate.

source Editorial team; facts: Webster's Revised Unabridged Dictionary, 1913; W. W. Skeat, An Etymological Dictionary of the English Language, 1910, open source

Arct (9th ed., 1921) records Ontologja as the science of being, a part of metaphysics, and Ontolog as an adherent of metaphysics. Under Metafizyka Arct notes philosophy that investigates the essence, cause and laws of all things and the most general principles of being, plus inquiry into what lies beyond sensory reality; colloquially: something hard to grasp, detached, intricate. That is 1920s lexical evidence, not this site's definition. From Arct only the lexical fact is taken. A separate Ontologiczny lemma was not caught in the OCR query used here.

source Editorial team; facts: M. Arct, Słownik wyrazów obcych, 9th ed., Warsaw 1921, open source

Writers often pair the lemma with philosophical, of being, question, commitment, or domain (comput.). Ontologist names an adherent; ontological and ontologic are related adjectives. Exact writers keep the lemma apart from metaphysics as a wider frame, from phenomenology as a register of appearances against theses on being as such, and from bare empirical reportage without claims about existence beyond sensory data. Borders still shift by author.

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Word forms

Regular English noun, usually uncountable; the plural ontologies is common in the computing register for distinct domain models, and less common in philosophy for rival systems or historical versions of the science of being.

word forms

przypadek forma
singular ontology
plural ontologies

Word forms: Editorial team

Collocations

Synonyms · Antonyms

Synonyms metaphysics proper / science of being (in Webster: ontology identified with metaphysics proper; partial range, not a full synonym of all metaphysics), science of being (in Arct: Ontologja = science of being, part of metaphysics; in Skeat: ONTOLOGY = the science of being), account of beings in the abstract (in Skeat / Bailey 1725: Account of Beings in the Abstract; historical gloss, not a modern synonym)
source Editorial team; facts: Webster's Revised Unabridged Dictionary, 1913 (Ontology; Metaphysics: ontology / metaphysics proper), open source
Antonyms science of phenomenal being / phenomenal side (in Webster: ontology as science of real being as distinguished from phenomenal being; didactic contrast), phenomenology (register of appearances against theses about being as such; contrastive neighbour, not a strict dictionary antonym), bare empiricism without theses about existence beyond sensory data (didactic contrast; editorial scope, to confirm at review)
source Editorial team; facts: Webster's Revised Unabridged Dictionary, 1913 (Metaphysics: science of real as distinguished from phenomenal being; ontology), open source

Etymology

English ontology joins a Greek base for being with the -logy ending ("study, account"). Skeat 1910 glosses ONTOLOGY as "the science of being" and quotes Bailey's early eighteenth century line on an Account of Beings in the Abstract, with the Greek split ὀντο- (from the present participle stem of εἶναι "to be") + -λογία (from λόγος, from λέγειν "to speak"). Webster 1913 records Ontology with a Greek etymology and cf. F. ontologie, and frames it as a branch of metaphysics devoted to beings considered in themselves, their essential traits and ties. Nearby lemmas include Ontologist, Ontological and Ontologic. Arct 1921 notes Ontologja (science of being, part of metaphysics) and Ontolog (adherent of metaphysics). Editorial senses above are drafted apart from those dictionary wordings. A related Polish noun is ontologia.
source Webster's Revised Unabridged Dictionary, 1913, open source
also W. W. Skeat, An Etymological Dictionary of the English Language, 4th ed., Oxford 1910, open source
also M. Arct, Słownik wyrazów obcych, 9th ed., Warsaw 1921, open source

Related words

Related entries

Questions and answers

What does ontology mean in philosophy, and what in computing?

In philosophy the name covers the science of being inside metaphysics: claims about what exists and about principles of being. In computing and knowledge engineering it often labels a formal description of concepts and relations in a domain. Those are two registers: classical metaphysical and contemporary technical. Scope follows context.

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Where does the word ontology come from?

The base is Greek: ὀντο- (from the present participle of εἶναι "to be") plus -λογία / -logy (from λόγος, λέγειν "to speak"). Skeat 1910 records ONTOLOGY ("science of being") and Bailey (1725). Webster 1913 has Ontology (cf. F. ontologie). Arct 1921 notes Ontologja and Ontolog. The English lemma follows that path.

source Editorial team; facts: Webster 1913; W. W. Skeat, An Etymological Dictionary of the English Language, 1910; M. Arct, Słownik wyrazów obcych, 1921, open source

How does ontology differ from metaphysics and phenomenology?

In Webster Ontology is a department of metaphysics about being; Metaphysics is often the wider frame, and ontology is sometimes called metaphysics proper. Phenomenology is a description or explanation of phenomena. In Arct Ontologja is the science of being (part of metaphysics), and Fenomenologia names the phenomenal side. Casual talk confuses all three with "general philosophy of reality".

source Editorial team; facts: Webster 1913 (Ontology, Metaphysics, Phenomenology); M. Arct 1921 (Ontologja, Fenomenologia, Metafizyka), open source

What are the word forms of ontology?

The noun is regular and usually uncountable: ontology. A plural ontologies turns up often in computing (separate domain models) and less often in philosophy for rival systems or historical versions. Related forms include ontologist (adherent) and ontological / ontologic.

source Editorial team (in-house source, no external address)