Standard Lemma guide

ill-defined

adj · 3 senses · updated from the 2026-07-25 local source snapshot

Definitions and examples are grouped by meaning. Pronunciation, history, word forms, translations, descendants, synonyms, antonyms, derived terms, and related words appear whenever the source provides them.

Sound

Pronunciation

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1

adj

Meaning 1

Poorly defined; blurry, out of focus; lacking a clear boundary.

Definition source: English Wiktionary via Wiktextract

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

2

adj

Meaning 2

Defined in an inconsistent way.

Definition source: English Wiktionary via Wiktextract

Topics: mathematics, sciences

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

3

adjective

Meaning 3

poorly stated or described

Definition source: Princeton WordNet 3.0

Examples

  • he confuses the reader with ill-defined terms and concepts

Meaning relationships

Synonyms: unclear

Antonyms: well-defined

History

Etymology

From ill + defined.

Real reading context

ill-defined in complete knowledge articles