valvetop: closed check valvebottom: open check valvevalve (v?lv)n.1. a. Any of various devices that regulate the flow of gases, liquids, or loose materials through piping or through apertures by opening, closing, or obstructing ports or passageways.b. The movable control element of such a device.c. A device in a brass wind instrument that can be opened or closed to change the pitch by altering the length of the air column in the tube.2. Anatomy A membranous structure in a hollow organ or passage, as in an artery or vein, that folds or closes to prevent the return flow of the body fluid passing through it.3. Biology a. A piece of shell covering or enclosing certain mollusks or other invertebrates, especially the single one of a univalve mollusk or one of the paired hinged ones of a bivalve mollusk or brachiopod.b. One of the two siliceous halves of the cell wall of a diatom.4. One of the pieces into which a plant part splits at maturity, especially a segment of a fruit capsule or of certain anthers.5. Chiefly British An electron tube or a vacuum tube.6. Archaic Either half of a double or folding door.tr.v. valved, valv·ing, valves 1. To provide with a valve.2. To control by means of a valve.[Middle English, leaf of a door, from Latin valva; see wel- in Indo-European roots.]valve?less adj.American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
-valved
valvetop: closed check valvebottom: open check valvevalve (v?lv)n.1. a. Any of various devices that regulate the flow of gases, liquids, or loose materials through piping or through apertures by opening, closing, or obstructing ports or passageways.b. The movable control element of such a device.c. A device in a brass wind instrument that can be opened or closed to change the pitch by altering the length of the air column in the tube.2. Anatomy A membranous structure in a hollow organ or passage, as in an artery or vein, that folds or closes to prevent the return flow of the body fluid passing through it.3. Biology a. A piece of shell covering or enclosing certain mollusks or other invertebrates, especially the single one of a univalve mollusk or one of the paired hinged ones of a bivalve mollusk or brachiopod.b. One of the two siliceous halves of the cell wall of a diatom.4. One of the pieces into which a plant part splits at maturity, especially a segment of a fruit capsule or of certain anthers.5. Chiefly British An electron tube or a vacuum tube.6. Archaic Either half of a double or folding door.tr.v. valved, valv·ing, valves 1. To provide with a valve.2. To control by means of a valve.[Middle English, leaf of a door, from Latin valva; see wel- in Indo-European roots.]valve?less adj.American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.valve (vælv) n1. (Mechanical Engineering) any device that shuts off, starts, regulates, or controls the flow of a fluid2. (Anatomy) anatomy a flaplike structure in a hollow organ, such as the heart, that controls the one-way passage of fluid through that organ3. (Electronics) Also called: tube or vacuum tube an evacuated electron tube containing a cathode, anode, and, usually, one or more additional control electrodes. When a positive potential is applied to the anode, electrons emitted from the cathode are attracted to the anode, constituting a flow of current which can be controlled by a voltage applied to the grid to produce amplification, oscillation, etc. See also diode2, triode1, tetrode, pentode4. (Zoology) zoology any of the separable pieces that make up the shell of a mollusc5. (Music, other) music a device on some brass instruments by which the effective length of the tube may be varied to enable a chromatic scale to be produced6. (Botany) botany a. any of the several parts that make up a dry dehiscent fruit, esp a capsuleb. either of the two halves of a diatom cell wall7. (Architecture) archaic a leaf of a double door or of a folding door[C14: from Latin valva a folding door] ?valveless adj ?valve?like adjCollins English Dictionary ? Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014valve (vælv) n., v. valved, valv?ing. n. 1. any device for halting or controlling the flow of something, as a liquid, through a pipe or other passage. 2. a hinged lid or other movable part that closes or modifies the passage in such a device. 3. a membranous structure that permits the flow of a fluid, as blood, in one direction only. 4. (in brass instruments) a device for changing the length of the air column to alter the pitch of a tone. 5. one of the two or more separable pieces composing certain shells: the valves of a clamshell. 6. Bot. a. one of the segments into which a fruit capsule dehisces. b. a flap or lidlike part of certain anthers. 7. Chiefly Brit. vacuum tube. 8. Archaic. one of the leaves of a double or folding door. v.t. 9. to provide with a valve. [1350?1400; Middle English