whimsy
noun/ˈwɪmzi/
/ˈwɪmzi/
[uncountable]- a way of thinking or behaving or a style of doing something that is unusual and not serious, in a way that is either funny or annoying
怪念头；古怪可笑的举动；吊儿郎当；随心所欲 Word Originearly 17th cent. (in the sense ‘caprice’): probably based on whim-wham, a whim.