undefinable

adj

"undefinable" is a 11-letter English headword indexed on PlainSpell.

The verdict

“undefinable” is uncommon English (outside the top frequency list), classed as an adjective. The kind of spelling people second-guess.

Unranked
below top-frequency English
11
letters

According to Wiktionary data (CC BY-SA, analyzed September 3, 2026) - Not definable.

Corpus desk

Index EN-undefinable · undefinable · English

undefinable · unranked · 0 variants · 0 confusables

  • FREQ-UNRANKED Unranked
  • LEN-MEGA 11 letters
  • VOW-5 5 vowels
  • CONFUS-0 No pairs
  • VAR-0 0 variants
  • BOOK-THIN "U" thin
  • PHOTO-UNK Peer pending

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.

Key facts for undefinable
PropertyValue
Headwordundefinable
LanguageEnglish
Part of speechAdjective
Letters11
Misspellings tracked0
Confusable pairs0
SourceWiktionary (kaikki.org)

Long-tail rank of “undefinable” in English

undefinablefalls outside the top-100,000 ranked English words, the long-tail zone of technical, archaic, or low-frequency vocabulary, exactly where readers second-guess spellings most.

Beyond rank #100,000. Source: FrequencyWords open word-frequency list.

Rare enough to double-check

undefinable is uncommon English outside the top frequency list, classed as anadjective. Rarity is why readers land here mid-draft. Gloss: "Not definable.".

undefinable doesn't appear in our generated misspelling index, typically a sign the spelling maps closely to how the word sounds. Our confusable-pair dataset has no match for it, since no other headword is close enough in sound or shape to pair with it.

Etymologically, the entry records: From un- + definable. The correct English form is undefinable, spelled U-N-D-E-F-I-N-A-B-L-E.

Definition

  1. 1
    Not definable.

Recorded use

Wiktionary example

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

  1. There was some little undefinable coolness between old General Chattesworth and Devereux. He admired the young fellow, and he liked good blood in his corps, but somehow he was glad when he thought he was likely to go.

Etymology

From un- + definable.

Synonyms

Definitions, pronunciation, and etymology for this entry are drawn from Wiktionary via the kaikki.org structured extract (CC BY-SA). See the methodology for how each field is sourced and updated.

Frequently Asked Questions

How do you spell "undefinable"?
"undefinable" is spelled U-N-D-E-F-I-N-A-B-L-E.
What does "undefinable" mean?
As an adjective, "undefinable" means: Not definable.
What is the origin of the word "undefinable"?
From un- + definable. 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.

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

Source: FrequencyWords open word-frequency list