frívolo, insustancial, nimio, pueril, superficial, trivial, vacuo
baladí, insignificante, insustancial, ligero, pueril, somero, superficial, trivial
anodino, común, corriente, gris, insignificante, insípido, insulso, insustancial, mediocre, nimio, ordinario, regular, soso, trivial, vulgar