valve

one of the paired hinged shells of certain molluscs and of brachiopods

某些软体动物和腕足动物的成对铰链壳之一

the entire one-piece shell of a snail and certain other molluscs

蜗牛和某些其他软体动物的整个一块壳

control consisting of a mechanical device for controlling the flow of a fluid

由控制流体流动的机械装置组成的控制装置

device in a brass wind instrument for varying the length of the air column to alter the pitch of a tone

铜管乐器中的一种装置，用于改变气柱的长度以改变音调

a structure in a hollow organ (like the heart) with a flap to insure one-way flow of fluid through it

中空器官（如心脏）中的一种结构，有一个瓣以确保液体单向流动