unclear

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

Synonyms

• ill-definedpoorly stated or described

• "the law itself was unclear on that point"
• "the reason for their actions is unclear to this day"

• "indecipherable handwriting"

Synonyms

• indecipherablenot easily deciphered; impossible to determine the meaning of
• undecipherablenot easily deciphered
• unreadablenot easily deciphered