ill-defined

English

Etymology

From ill +‎ defined.

Adjective

ill-defined (comparative more ill-defined, superlative most ill-defined)

1. Poorly defined; blurry, out of focus; lacking a clear boundary.
   • 1837, L[etitia] E[lizabeth] L[andon], Ethel Churchill: Or, The Two Brides. […], volume III, London: Henry Colburn, […], →OCLC, pages 45–46:

     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.

   • 2020, Myles McCabe, “Stellar Abattoir”, in Triceratops, performed by ME REX:

     Are you sick, or ill-defined? / Are you lost, or are you just difficult to come by?

2. (mathematics) Defined in an inconsistent way.

Synonyms

• (poorly defined): fuzzy, hazy; see also Thesaurus:indistinct
• (defined in an inconsistent way):

Antonyms

• well-defined

Hyponyms

• defined

Derived terms

• ill-definedness