Synonyms: empty-headed, featherbrained, giddy, light-headed, lightheaded, dizzy, silly, airheaded
Definition: lacking seriousness; given to frivolity
Usage: a dizzy blonde; light-headed teenagers; silly giggles
Similar words: frivolous
Definition: not serious in content or attitude or behavior
Usage: a frivolous novel; a frivolous remark; a frivolous young woman