/ˈbʌtəflaɪ ||; ˈbʌtɚˌflaɪ/noun1 [C] (plural butterflies) an insect with a long, thin body and four brightly coloured wings 蝴蝶: Caterpillars develop into butterflies. 毛虫蜕变为蝴蝶。 ☞picture at insect 见 insect 插图
2 [U] a style of swimming in which both arms are brought over the head at the same time, and the legs move up and down together 蝶泳；蝶式
have butterflies (in your stomach)(
informal 非正式) to feel very nervous before doing sth 行动之前忐忑不安