Source : WordNet®

unclear
     adj 1: poorly stated or described; "he confuses the reader with
            ill-defined terms and concepts" [syn: {ill-defined}]
            [ant: {well-defined}]
     2: not clear to the mind; "the law itself was unclear on that
        point"; "the reason for their actions is unclear to this
        day" [ant: {clear}]
     3: not easily deciphered; "indecipherable handwriting" [syn: {indecipherable},
         {undecipherable}, {unreadable}]