(of people or their behaviour 人或行为 silly or funny, especially when such behaviour is not suitable 愚蠢的；可笑的 having no useful or serious purpose 无聊的；不严肃的 frivolous pastimes/pleasures 无聊的消遣／娱乐
Word Originlate Middle English: from Latin frivolus ‘silly, trifling’ + -ous.