Source : WordNet®

uninstructive
     adj 1: not tending to inform or clarify; "an unenlightening
            comment" [syn: {unenlightening}, {uninformative}]
            [ant: {enlightening}]
     2: not informative or enlightening [syn: {uninformative}] [ant:
         {instructive}]
     3: not informative [syn: {uninformative}] [ant: {informative}]