Source : WordNet®

flighty
     adj 1: irresponsibly frivolous; "flighty young girls" [syn: {flyaway}]
     2: absent-mindedly irresponsible; "he said I was too flighty to
        be a good supervisor" [syn: {head-in-the-clouds}, {scatterbrained}]
     [also: {flightiest}, {flightier}]

flightiest
     See {flighty}