Source : WordNet®

unmusical
     adj 1: lacking interest in or talent for music; "too unmusical to
            care for concerts"; "it is unfortunate that her
            children were all nonmusical" [syn: {nonmusical}]
            [ant: {musical}]
     2: not musical in nature; "the unmusical cry of the bluejay"
        [syn: {nonmusical}, {dissonant}] [ant: {musical}]
     3: lacking melody [syn: {unmelodious}, {unmelodic}] [ant: {melodious}]