ontology

/ɒnˈtɒləd͡ʒi/

//ɒnˈtɒləd͡ʒi// noun

By · According to Wiktionary data (CC BY-SA) ·

"ontology" is a 8-letter English headword indexed on PlainSpell.

The verdict

“ontology” has 12 generated spelling variants in the English index at frequency #31,275. The variants make it a useful spelling check.

#31,275
frequency rank, English
15,494
“O” headwords
12
tracked misspellings
1
confusable pair

According to Wiktionary data (CC BY-SA, analyzed May 6, 2026) - The branch of metaphysics that addresses the nature or essential characteristics of being and of things that exist; the study of being qua being.

Visual similarity to commonly confused words

How many letter changes separate each confused pair (Levenshtein distance, normalized).

ontology vs oncology
88% similar

Source: PlainSpell confusable corpus (Wiktionary, CC BY-SA).

Key facts for ontology
PropertyValue
Headwordontology
LanguageEnglish
Part of speechNoun
IPA/ɒnˈtɒləd͡ʒi/
Letters8
Frequency rank#31,275
Misspellings tracked12
Confusable pairs1
SourceWiktionary (kaikki.org)

Where “ontology” sits in English frequency

Every-word frequency runs from the handful of words we use constantly (left) to the long tail used once in a blue moon (right). ontology lands here:

#1#100#1K#10K#100K
← used constantlyrarely used →

Scale is logarithmic (each tick is 10× rarer). Source: FrequencyWords open word-frequency list.

A misspelling magnet

The generator records 12 spelling variants around ontology (IPA /ɒnˈtɒləd͡ʒi/), anoun. Corpus frequency is #31,275 among 15,494 “O” headwords. Wiktionary lists 5 senses, so context still picks the gloss.

Our generated misspelling index lists 12 likely wrong-spelling variants for ontology, with forms such as "notology", "onntology", and "onotlogy". Each variant is a distinct typo pattern an edit-distance generator flags, typically a doubled-consonant error, a silent-letter drop, or a vowel substitution. It also participates in 1 confusable-pair relationship, "oncology", since the words sound or look close enough that writers reach for the wrong one mid-sentence.

Etymologically, the entry records: Learned borrowing from New Latin ontologia (1606, Ogdoas Scholastica, by Jacob Lorhard (Lorhardus)), from Ancient Greek ὤν, ὄντος (ṓn, óntos, “being”), present participle of εἰμί (eimí, “being, existing, essence”) + λόγος (lógos, “account”). By surface anal… The correct English form is ontology, spelled O-N-T-O-L-O-G-Y.

Definition

  1. 1
    The branch of metaphysics that addresses the nature or essential characteristics of being and of things that exist; the study of being qua being.
  2. 2
    In a subject view, or a world view, the set of conceptual or material things or classes of things that are recognised as existing, or are assumed to exist in context, and their interrelations; in a body of theory, the ontology comprises the domain of discourse, the things that are defined as existing, together with whatever emerges from their mutual implications.
  3. 3
    The theory of a particular philosopher or school of thought concerning the fundamental types of entity in the universe.
  4. 4
    A logical system involving theory of classes, developed by Stanislaw Lesniewski (1886-1939).
  5. 5
    A structure of concepts or entities within a domain, organized by relationships; a system model.

Etymology

Learned borrowing from New Latin ontologia (1606, Ogdoas Scholastica, by Jacob Lorhard (Lorhardus)), from Ancient Greek ὤν, ὄντος (ṓn, óntos, “being”), present participle of εἰμί (eimí, “being, existing, essence”) + λόγος (lógos, “account”). By surface analysis, onto- + -logy. First known English use 1663: Archelogia philosophica nova; or, New principles of Philosophy. Containing Philosophy in general, Metaphysicks or Ontology, Dynamilogy or a Discourse of Power, Religio Philosophi or Natural Theology, Physicks or Natural philosophy, by Gideon Harvey (1636–1702), London, Thomson, 1663. Popularized as a philosophical term by German philosopher Christian Wolff (1679–1754).

This word in other languages

ontología(Español)ontologie(Français)Ontologie(Deutsch)

Common misspellings

Also misspelled as:

  • notology
  • onntology
  • onotlogy
  • ontloogy
  • ontolgoy
  • ontollogy
  • ontologgy
  • ontologyy
  • ontoloyg
  • ontoolgy
  • onttology
  • otnology

Misspelling Pattern Breakdown

How far each generated variant is from the correct spelling of ontology - expressed in single-character edits (insert, delete, or swap one letter). Bigger bars stand out at a glance; a one-edit slip is the hardest to catch.

notology2onntology1onotlogy2ontloogy2ontolgoy2ontollogy1ontologgy1ontologyy1
Edit distance from "ontology"

Definitions, pronunciation, and etymology for this entry are drawn from Wiktionary via the kaikki.org structured extract (CC BY-SA); frequency ordering uses the FrequencyWords open word-frequency list (2018 English corpus, MIT). See the methodology for how each field is sourced and updated.

Frequently Asked Questions

How do you spell "ontology"?
"ontology" is spelled O-N-T-O-L-O-G-Y. The IPA pronunciation is /ɒnˈtɒləd͡ʒi/.
What does "ontology" mean?
As a noun, "ontology" means: The branch of metaphysics that addresses the nature or essential characteristics of being and of things that exist; the study of being qua being.
What words are commonly confused with "ontology"?
"ontology" is commonly confused with "oncology". These words look or sound similar but have different meanings. PlainSpell provides detailed comparisons for each pair.
How do you pronounce "ontology"?
The IPA (International Phonetic Alphabet) transcription for "ontology" is /ɒnˈtɒləd͡ʒi/. Click the speaker icon on the pronunciation badge above to hear it spoken aloud where audio is available.
What is the origin of the word "ontology"?
Learned borrowing from New Latin ontologia (1606, Ogdoas Scholastica, by Jacob Lorhard (Lorhardus)), from Ancient Greek ὤν, ὄντος (ṓn, óntos, “being”), present participle of εἰμί (eimí, “being, existing, essence”) + λόγος (lógos, “account”). By su... See the full etymology section above for more details.
Is PlainSpell free to use?
Yes, PlainSpell is a completely free word reference. You can look up definitions, pronunciations, confusable pairs, homophones, and spelling corrections across 5 languages without any sign-up or subscription.

Using “ontology”

The practical upshot for anyone who landed here from a spell-check.

  • The one correct English spelling is O-N-T-O-L-O-G-Y - every other letter order is a misspelling in standard orthography.
  • Say it as /ɒnˈtɒləd͡ʒi/ (IPA); tap the speaker on the pronunciation badge to hear it where audio exists.
  • Don't mix it up with “oncology” - see the side-by-side comparison. ontology vs oncology
  • Browse more English words and confusable pairs in the same reference. English words

Same frequency band

Data Source

Wiktionary (via kaikki.org), licensed under CC BY-SA & GFDL. Word ordering uses an open word-frequency list; misspelling variants are generated by edit-distance from the correct headword.

Source: Wiktionary (via kaikki.org) Structured Wiktionary extract

Source: FrequencyWords open word-frequency list FrequencyWords open word-frequency list