backswimmer / ˈbækˌswɪm ər /

📖毕业后词汇仰卧起坐者仰卧起坐的人仰泳者仰卧起坐

backswimmer 的定义

n. 名词 noun
  1. any of numerous predaceous aquatic hemipterous insects, of the family Notonectidae, that swim on their backs, and may inflict a painful bite if handled.