tautology

/toːˈtɔl.ə.d͡ʒi/

//toːˈtɔl.ə.d͡ʒi// noun

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

"tautology" is a 9-letter English headword indexed on PlainSpell.

The verdict

“tautology” is uncommon English (frequency #71,965 among 27,828 “T” headwords), classed as a noun. The kind of spelling people second-guess.

#71,965
frequency rank, English
27,828
“T” headwords

According to Wiktionary data (CC BY-SA, analyzed May 6, 2026) - Redundant use of words, a pleonasm, an unnecessary and tedious repetition.

Key facts for tautology
PropertyValue
Headwordtautology
LanguageEnglish
Part of speechNoun
IPA/toːˈtɔl.ə.d͡ʒi/
Letters9
Frequency rank#71,965
Misspellings tracked0
Confusable pairs0
SourceWiktionary (kaikki.org)

Where “tautology” 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). tautology lands here:

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

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

Rare enough to double-check

tautology is uncommon English at frequency #71,965 among 27,828 “T” headwords, classed as anoun, transcribed /toːˈtɔl.ə.d͡ʒi/. Rarity is why readers land here mid-draft. 4 senses are on record.

We couldn't generate a plausible misspelling set for tautology, since its letter sequence doesn't invite the usual edit-distance slips. It is not paired with a close-neighbour confusable in our dataset, since nothing in our dataset looks or sounds close enough to cause mix-ups.

Etymologically, the entry records: From Late Latin tautologia, from Ancient Greek ταὐτολογία (tautología) from ταὐτός (tautós, “the same”) + λόγος (lógos, “explanation”). By surface analysis, tauto- + -logy. The correct English form is tautology, spelled T-A-U-T-O-L-O-G-Y.

Definition

  1. 1
    Redundant use of words, a pleonasm, an unnecessary and tedious repetition.
  2. 2
    An expression that features tautology.
  3. 3
    A statement that is true for all truth values of its propositional variables.
  4. 4
    A statement that is true for all truth values of its Boolean atoms.

Etymology

From Late Latin tautologia, from Ancient Greek ταὐτολογία (tautología) from ταὐτός (tautós, “the same”) + λόγος (lógos, “explanation”). By surface analysis, tauto- + -logy.

Antonyms

contradiction in termscontradictionoxymoron

This word in other languages

tautología(Español)tautologie(Français)Pleonasmus(Deutsch)tautologia(Português)

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 "tautology"?
"tautology" is spelled T-A-U-T-O-L-O-G-Y. The IPA pronunciation is /toːˈtɔl.ə.d͡ʒi/.
What does "tautology" mean?
As a noun, "tautology" means: Redundant use of words, a pleonasm, an unnecessary and tedious repetition.
How do you pronounce "tautology"?
The IPA (International Phonetic Alphabet) transcription for "tautology" is /toːˈtɔl.ə.d͡ʒi/. 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 "tautology"?
From Late Latin tautologia, from Ancient Greek ταὐτολογία (tautología) from ταὐτός (tautós, “the same”) + λόγος (lógos, “explanation”). By surface analysis, tauto- + -logy. 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 “tautology”

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

  • The one correct English spelling is T-A-U-T-O-L-O-G-Y - every other letter order is a misspelling in standard orthography.
  • Say it as /toːˈtɔl.ə.d͡ʒi/ (IPA); tap the speaker on the pronunciation badge to hear it where audio exists.
  • Browse more English words and confusable pairs in the same reference. English words

Other uncommon English words near this rank

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