stopcocks

英 [ˈstɒpkɒks]

美

n.  (调节管道流量的)旋塞，活栓
stopcock的复数

柯林斯词典

• 活塞;活栓;旋塞阀
  Astopcockis a tap on a pipe, which you turn in order to allow something to pass through the pipe or to stop it from passing through.