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 3,151 “T” headwords), classed as a noun. The kind of spelling people second-guess.

#71,965
frequency rank, English
3,151
“T” headwords

According to Wiktionary data (CC BY-SA, analyzed September 3, 2026) - Redundant use of words, a pleonasm, an unnecessary and tedious repetition.

Corpus desk

Index EN-tautology · tautology · English

tautology · rank #71,965 · 0 variants · 0 confusables

  • FREQ-RARE #71,965
  • LEN-LONG 9 letters
  • VOW-5 5 vowels
  • CONFUS-0 No pairs
  • VAR-0 0 variants
  • BOOK-MID 3,151
  • PHOTO-FINISH tatami

Nearest frequency peer: tatami (-1 rank slots)

Read with this headword: Spelling guide for this pattern

Desk codes from Wiktionary headword shape, FrequencyWords rank tier, confusable-pair count, generated misspelling depth, letter-cohort book size, and photo-finish peer. Not a difficulty grade.

Long-tail ranks near “tautology”

Sparse band: bars invert rank so rarer forms read shorter

corpus weight

What this shows Long-tail view: where “tautology” sits against similarly uncommon English ranks.

Source FrequencyWords open word-frequency list As of September 3, 2026
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)

Long-tail rank of “tautology” in English

This scale runs from the tiny cluster of words that carry ordinary speech (left) to the long tail of words almost nobody reaches for (right).tautologyfalls in this rarity band:

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

The axis is logarithmic, with each marked tick roughly ten times rarer than the last. Rare peers in the same band: “tatami” (#71,964), “Tannenbaum” (#71,962), “TANF” (#71,961). Among 3,151 “T” headwords, “tautology” is #71,965. Source: FrequencyWords open word-frequency list.

Rare enough to double-check

tautology is uncommon English at frequency #71,965 among 3,151 “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.

Recorded use

Wiktionary examples

These source excerpts show how tautology appears in context. They illustrate usage; the definition above remains the entry’s reference meaning.

  1. It is tautology to say, "Forward Planning".
  2. The expression "raze to the ground" is a tautology, since the word "raze" includes the notion "to the ground".

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.

Similar English words by spelling shape

Same letter count and similar misspelling depth for "tautology", not the corpus desk frequency band.

Same letter count

Frequency-ranked English headwords with 9 letters (nearest by frequency rank).

sniffling#71,932underling#71,998unreality#72,006varicella#72,014

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

Source: FrequencyWords open word-frequency list