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valve
valve / valv/ • n. a device for controlling the passage of fluid through a pipe or duct, esp. an automatic device allowing movement in one direction only. ∎ (in full ther·mi·on·ic valve) Electr. British term for thermionic tube. ∎ Mus. a cylindrical mechanism in a brass instrument that, when depressed or turned, admits air into different sections of tubing and so extends the range of available notes. ∎ Anat. & Zool. a membranous fold in a hollow organ or tubular structure, such as a blood vessel or the digestive tract, that maintains the flow of the contents in one direction by closing in response to any pressure from reverse flow. ∎ Zool. each of the halves of the hinged shell of a bivalve mollusk or brachiopod, or of the parts of the compound shell of a barnacle. ∎ Bot. each of the halves or sections into which a dry fruit (esp. a pod or capsule) dehisces.
DERIVATIVES: valved adj. [in comb.] a branchiopod has a two-valved outer covering valve·less adj. valve |
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"valve." The Oxford Pocket Dictionary of Current English. 2009. Encyclopedia.com. 10 Feb. 2012 <http://www.encyclopedia.com>. "valve." The Oxford Pocket Dictionary of Current English. 2009. Encyclopedia.com. (February 10, 2012). http://www.encyclopedia.com/doc/1O999-valve.html "valve." The Oxford Pocket Dictionary of Current English. 2009. Retrieved February 10, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O999-valve.html |
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valve
valve device for controlling the flow of fluids (liquids and gases). Valves vary in construction and size depending upon their function. Some are classified according to their method of operation or design, e.g., butterfly, gate, globe, lift, needle, piston, and slide valves. Valves are also named for the functions they perform, e.g., check valve (which permits flow in one direction only) and cutoff, bypass, exhaust, intake, safety (see safety valve ), and throttle valves. Valves are operated automatically, by hand, or by special mechanism. Valves are employed in the carburetor, diesel engine, internal-combustion engine, pump, and steam engine. In Great Britain an electron tube may be referred to as a valve. In anatomy and physiology the term valve includes the flaps of tissue that help to control the direction of the flow of blood in the heart. |
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"valve." The Columbia Encyclopedia, 6th ed.. 2008. Encyclopedia.com. 10 Feb. 2012 <http://www.encyclopedia.com>. "valve." The Columbia Encyclopedia, 6th ed.. 2008. Encyclopedia.com. (February 10, 2012). http://www.encyclopedia.com/doc/1E1-valve.html "valve." The Columbia Encyclopedia, 6th ed.. 2008. Retrieved February 10, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1E1-valve.html |
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valve
valve (Fr. piston; Ger. Ventil; It. pistone). Mechanism invented c.1813 by the horn-player Heinrich Stölzel and improved in 1818 in collaboration with Friedrich Blühmel, whereby all the notes of the chromatic scale were made available to brass instr. Pitch altered by increasing or decreasing length of tube through which wind must go to produce sound (except normal trombones, for which slide is sufficient). 2 types in use, piston, in which piston works up and down in casing, and rotary, a 4-way stop-cock turning in cylindrical case and governed by a spring. Credit for the first type of valve must go to Charles Clagget, an Irishman, who patented an invention in 1788 which enabled pitch to be altered by means of a lever.
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MICHAEL KENNEDY and JOYCE BOURNE. "valve." The Concise Oxford Dictionary of Music. 1996. Encyclopedia.com. 10 Feb. 2012 <http://www.encyclopedia.com>. MICHAEL KENNEDY and JOYCE BOURNE. "valve." The Concise Oxford Dictionary of Music. 1996. Encyclopedia.com. (February 10, 2012). http://www.encyclopedia.com/doc/1O76-valve.html MICHAEL KENNEDY and JOYCE BOURNE. "valve." The Concise Oxford Dictionary of Music. 1996. Retrieved February 10, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O76-valve.html |
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valve
valve
1. Any of various structures for restricting the flow of a fluid through an aperture or along a tube to one direction. Valves in the heart (see bicuspid valve; semilunar valve; tricuspid valve), veins, and lymphatic vessels consist of two or three flaps of tissue (cusps) fastened to the walls. The cusps are flattened to the walls to allow the normal passage of blood or lymph, but a reverse flow causes them to block the vessel or aperture, so preventing further backflow. 2. Any of the parts that make up a capsule or other dry fruit that sheds its seeds. 3. One of the two halves of the cell wall of a diatom. 4. Either of the two hinged portions of the shell of a bivalve mollusc. |
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"valve." A Dictionary of Biology. 2004. Encyclopedia.com. 10 Feb. 2012 <http://www.encyclopedia.com>. "valve." A Dictionary of Biology. 2004. Encyclopedia.com. (February 10, 2012). http://www.encyclopedia.com/doc/1O6-valve.html "valve." A Dictionary of Biology. 2004. Retrieved February 10, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O6-valve.html |
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valve
valve (valv) n. a structure found in some tubular organs or parts that restricts the flow of fluid within them to one direction only (see cusp). Valves are important structures in the heart, veins, and lymphatic vessels (see vein). See also aortic valve, mitral valve, pulmonary (valve), tricuspid valve.
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"valve." A Dictionary of Nursing. 2008. Encyclopedia.com. 10 Feb. 2012 <http://www.encyclopedia.com>. "valve." A Dictionary of Nursing. 2008. Encyclopedia.com. (February 10, 2012). http://www.encyclopedia.com/doc/1O62-valve.html "valve." A Dictionary of Nursing. 2008. Retrieved February 10, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O62-valve.html |
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valve
valve
1. One of the two halves of the hinged shell of brachiopods (Brachiopoda), or molluscs (Mollusca) of the class Bivalvia. 2. One half of the cell wall of a diatom. 3. A flap or other constriction that can close to ensure that a fluid flows in only one direction. |
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AILSA ALLABY and MICHAEL ALLABY. "valve." A Dictionary of Earth Sciences. 1999. Encyclopedia.com. 10 Feb. 2012 <http://www.encyclopedia.com>. AILSA ALLABY and MICHAEL ALLABY. "valve." A Dictionary of Earth Sciences. 1999. Encyclopedia.com. (February 10, 2012). http://www.encyclopedia.com/doc/1O13-valve.html AILSA ALLABY and MICHAEL ALLABY. "valve." A Dictionary of Earth Sciences. 1999. Retrieved February 10, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O13-valve.html |
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valves
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"valves." World Encyclopedia. 2005. Encyclopedia.com. 10 Feb. 2012 <http://www.encyclopedia.com>. "valves." World Encyclopedia. 2005. Encyclopedia.com. (February 10, 2012). http://www.encyclopedia.com/doc/1O142-valves.html "valves." World Encyclopedia. 2005. Retrieved February 10, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O142-valves.html |
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valve
valve either of the leaves of a folding door XIV; one of the halves of a hinged shell XVII; (anat.) membranous fold; device resembling a flap, lid, etc. — L. valva leaf of a door.
So valvular XVIII. f. valvula, dim. of L. valva. |
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T. F. HOAD. "valve." The Concise Oxford Dictionary of English Etymology. 1996. Encyclopedia.com. 10 Feb. 2012 <http://www.encyclopedia.com>. T. F. HOAD. "valve." The Concise Oxford Dictionary of English Etymology. 1996. Encyclopedia.com. (February 10, 2012). http://www.encyclopedia.com/doc/1O27-valve.html T. F. HOAD. "valve." The Concise Oxford Dictionary of English Etymology. 1996. Retrieved February 10, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O27-valve.html |
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valve
valve
1. One of the two halves of the hinged shell of Mollusca (e.g. Bivalvia and Polyplacophora). 2. A flap that can close to ensure that a fluid flows in only one direction (e.g. in a blood vessel or heart). 3. See OVIPOSITOR. |
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MICHAEL ALLABY. "valve." A Dictionary of Zoology. 1999. Encyclopedia.com. 10 Feb. 2012 <http://www.encyclopedia.com>. MICHAEL ALLABY. "valve." A Dictionary of Zoology. 1999. Encyclopedia.com. (February 10, 2012). http://www.encyclopedia.com/doc/1O8-valve.html MICHAEL ALLABY. "valve." A Dictionary of Zoology. 1999. Retrieved February 10, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O8-valve.html |
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valve
valve
1. One of the portions into which a fruit splits. 2. In a diatom (Bacillariophyta), a silica theca, either the epithecium or the hypothecium. |
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MICHAEL ALLABY. "valve." A Dictionary of Plant Sciences. 1998. Encyclopedia.com. 10 Feb. 2012 <http://www.encyclopedia.com>. MICHAEL ALLABY. "valve." A Dictionary of Plant Sciences. 1998. Encyclopedia.com. (February 10, 2012). http://www.encyclopedia.com/doc/1O7-valve.html MICHAEL ALLABY. "valve." A Dictionary of Plant Sciences. 1998. Retrieved February 10, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O7-valve.html |
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valve
valve
•multivalve, salve, valve
•lipsalve • check valve • univalve
•bivalve
•delve, helve, shelve, twelve
•absolve, devolve, evolve, exsolve, involve, revolve, solve
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"valve." Oxford Dictionary of Rhymes. 2007. Encyclopedia.com. 10 Feb. 2012 <http://www.encyclopedia.com>. "valve." Oxford Dictionary of Rhymes. 2007. Encyclopedia.com. (February 10, 2012). http://www.encyclopedia.com/doc/1O233-valve.html "valve." Oxford Dictionary of Rhymes. 2007. Retrieved February 10, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O233-valve.html |
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