Valve

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[编辑] 解释

n.活门, 阀门
［英］活门, 阀门 ( a structure that closes temporarily a passage or orifice or permits movement of fluid in one direction only)
［类］ liquid : valve / electric current : switch ( 液体用阀门控制 / 电流用开关控制)

noun

Etymology: Latin valva; akin to Latin volvere to roll — more at voluble
Date: 14th century
1. archaic a leaf of a folding or double door
2. \［New Latin valva, from Latin\］ a bodily structure (as the mitral valve) that closes temporarily a passage or orifice or permits movement of fluid in one direction only
3.
- a. any of numerous mechanical devices by which the flow of liquid, gas, or loose material in bulk may be started, stopped, or regulated by a movable part that opens, shuts, or partially obstructs one or more ports or passageways; also the movable part of such a device
- b. a device in a brass instrument for quickly channeling air flow through an added length of tube in order to change the fundamental tone by some definite interval
- c. chiefly British electron tube
4. \［New Latin valva, from Latin\］ one of the distinct usually hinged and movable pieces of which the shell of some shell-bearing animals (as lamellibranch mollusks, brachiopods, and barnacles) consists
5. \［New Latin valva, from Latin\］
- a. one of the segments or pieces into which a dehiscing capsule or legume separates
- b. the portion of various anthers (as of the barberry) resembling a lid
- c. one of the two encasing membranes of a diatom
? valved adjective
? valveless adjective