<adj.all> his rattlebrained crackpot ideas how rattlepated I am! I've forgotten what I came for
guided by whim and fancy
<adj.all> flighty young girls
Now with Four Weddings he begins to look the drollest, most appealingly scatterbrained hero in Western cinema. Charles (Grant) is the eternal best man.
Nor did the Volksoper chorus rise to the scathing precision of their music; they were indifferently co-ordinated and scatterbrained. Perhaps their focus was blunted by politeness.