valve — ODE · Shobdo

valve /valv

▸ noun

1 a device for controlling the passage of fluid or air through a pipe, duct, etc., especially an automatic device allowing movement in one direction only:

a valve shuts off the flow from the boiler when the water is hot enough.

▪ British English short for thermionic valve

▪ Music a cylindrical mechanism in a brass instrument which, when depressed or turned, admits air into different sections of tubing and so extends the range of available notes.

▪ Anatomy Zoology a membranous fold in a hollow organ or tubular structure, such as a blood vessel or the digestive tract, which maintains the flow of the contents in one direction by closing in response to any pressure from reverse flow:

the aortic valve.

2 Zoology each of the halves of the hinged shell of a bivalve mollusc or brachiopod, or of the parts of the compound shell of a barnacle.

▪ Botany each of the halves or sections into which a dry fruit (especially a pod or capsule) dehisces.

– DERIVATIVES

valved /valvd

/ adjective

[in combination] a branchiopod has a two-valved outer covering.

valveless /ˈvalvləs

/ adjective

valvule /ˈvalvjuːl

/ noun

– ORIGIN late Middle English (denoting a leaf of a folding or double door): from Latin valva.