Synonyms of the word 
ILL-DEFINED → UNCLEAR
ill-defined
- adj. Poorly defined; blurry, out of focus; lacking a clear boundary.
- adj. (mathematics) Defined in an inconsistent way.
unclear
- adj. Ambiguous; liable to more than one interpretation.
- adj. Not clearly or explicitly defined.
- adj. Not easy to see or read; indecipherable or unreadable.
- adj. Not having a clear idea; uncertain.
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