frivolous Synonyms

worthless petty slight trivial trifling simplistic yeasty unimportant irrelevant unnecessary directionless airheaded empty-headed whimsical volatile vertiginous skin-deep skittish sleeveless stupid superficial thoughtless twopenny unconsequential featherbrained lightheaded recreational small-time noncritical uncritical nonobligatory birdbrained rattlebrained scatterbrained unappreciated unmeritorious unpersuasive nickel-and-dime Mickey Mouse meaningless tongue-in-cheek shoestring lighthearted lightweight footling piffling swingy penny ante harebrained devil-may-care