ill-defined
"ill-defined" is a 10-letter English headword indexed on PlainSpell.
The verdict
“ill-defined” 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) - Poorly defined; blurry, out of focus; lacking a clear boundary.
Corpus desk
Index EN-ill-defined · ill-defined · English
ill-defined · unranked · 0 variants · 0 confusables
- FREQ-UNRANKED Unranked
- LEN-MEGA 11 letters
- VOW-4 4 vowels
- CONFUS-0 No pairs
- VAR-0 0 variants
- BOOK-THIN "I" 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.
| Property | Value |
|---|---|
| Headword | ill-defined |
| Language | English |
| Part of speech | Adjective |
| Letters | 11 |
| Misspellings tracked | 0 |
| Confusable pairs | 0 |
| Source | Wiktionary (kaikki.org) |
Where “ill-defined” sits in English frequency
Rare enough to double-check
ill-defined is uncommon English outside the top frequency list, classed as anadjective. Rarity is why readers land here mid-draft. 2 senses are on record.
Zero misspellings are on record for ill-defined in our index, which points to an orthography that plays by predictable English rules. This headword has no recorded confusable partner, suggesting its spelling stands apart enough that readers rarely confuse it with something else.
Etymologically, the entry records: From ill + defined. The correct English form is ill-defined, spelled I-L-L---D-E-F-I-N-E-D.
Definition
- 1Poorly defined; blurry, out of focus; lacking a clear boundary.
- 2Defined in an inconsistent way.
Recorded use
Wiktionary examplesThese source excerpts show how ill-defined appears in context. They illustrate usage; the definition above remains the entry’s reference meaning.
An ill-defined dislike, a little like jealousy, arose in Henrietta's mind; a little, however, mitigated by observing that the gentleman instantly caught sight of herself; and that, when not absolutely forced to look at his companion, he looked towards her.
Are you sick, or ill-defined? / Are you lost, or are you just difficult to come by?
Etymology
From ill + defined.
Synonyms
Antonyms
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
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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.