gray


gray
The SI unit of absorbed dose of ionizing radiation, equivalent to 1 J/kg of tissue; 1 Gy = 100 rad. SYN: griseus. [Louis H. G., British radiologist, 1905–1965]

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gray or chiefly Brit grey 'grā n any of a series of neutral colors ranging between black and white
gray or chiefly Brit grey adj
gray 'grā n the mks unit of absorbed dose of ionizing radiation equal to an energy of one joule per kilogram of irradiated material abbr. Gy
Gray Louis Harold (1905-1965)
British radiobiologist. In 1933 Gray established a physics laboratory to measure radiation in the treatment of cancer at Mount Vernon Hospital, Middlesex, England. Earlier he and Sir W. H. Bragg had formulated a theory for deducing the energy absorbed by a material exposed to gamma rays from the ionization within a small gas-filled cavity in the material. At Mount Vernon he was to apply his theory to X-rays and later, in modified form, to neutrons. Gray expressed the neutron dose values in energy units, anticipating the International Commission on Radiological Units, which in 1953 adopted the rad as the unit for measuring all types of ionizing radiation. In 1975 the Commission adopted the gray as the physical unit of dose.

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n.
the SI units of absorbed dose of ionizing radiation, being the absorbed dose when the energy per unit mass imparted to matter by ionizing radiation is 1 joule per kilogram. It has replaced the rad. Symbol: Gy.

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(gra) 1. of a hue between white and black. 2. a unit of absorbed radiation dose equal to 100 rads. Abbreviated Gy.

Medical dictionary. 2011.

Synonyms:

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  • gray — gray …   Dictionnaire des rimes

  • Gray — puede referirse a: Contenido 1 Apellido 1.1 Personajes 1.1.1 Botánicos[1] 2 Divisiones administrativas …   Wikipedia Español

  • Gray — (gr[=a]), a. [Compar. {Grayer}; superl. {Grayest}.] [OE. gray, grey, AS. gr[=ae]g, gr[=e]g; akin to D. graauw, OHG. gr[=a]o, G. grau, Dan. graa, Sw. gr[*a], Icel. gr[=a]r.] [Written also {grey}.] 1. any color of neutral hue between white and… …   The Collaborative International Dictionary of English

  • Gray — 〈[grɛı] n. 15; 〉 Einheit für die Energiedosis ionisierender Strahlen, 1 Gy = 1 J/kg = 100 rad [nach dem amerikan. Physiker Louis Harold Gray, 1905 1965] * * * Gray [greɪ; nach dem brit. Physiker L. H. Gray (1905–1965)], das; s; Einheitenzeichen:… …   Universal-Lexikon

  • gray — [ grɛ ] n. m. • 1975; de Stephen Gray ♦ Métrol. Unité de mesure de dose absorbée de radiation (symb.Gy) communiquant à 1 kg de matière irradiée une énergie de 1 joule. ⇒ rad. ⊗ HOM. Grès. ● gray nom masculin (de Louis Harold Gray, nom propre)… …   Encyclopédie Universelle

  • GRAY (T.) — GRAY THOMAS (1716 1771) Solitaire et mélancolique, grand admirateur de la nature «sauvage», Thomas Gray, l’un des grands noms de la poésie anglaise du XVIIIe siècle, manifesta aussi un intérêt profond pour les littératures celtique et nordique,… …   Encyclopédie Universelle

  • Gray — Gray, GA U.S. city in Georgia Population (2000): 1811 Housing Units (2000): 713 Land area (2000): 2.418527 sq. miles (6.263956 sq. km) Water area (2000): 0.009479 sq. miles (0.024550 sq. km) Total area (2000): 2.428006 sq. miles (6.288506 sq. km) …   StarDict's U.S. Gazetteer Places

  • Gray — /gray/, n. 1. Asa /ay seuh/, 1810 88, U.S. botanist. 2. Thomas, 1716 71, English poet. * * * (as used in expressions) gray fox Gray Asa Gray Thomas Otis Harrison Gray Anne Gray Harvey * * * ▪ physics       unit of absorbed dose of i …   Universalium

  • gray — gray; gray·ish; gray·ling; gray·ness; gray·son; gray·wacke; gray·ly; ti·gray; …   English syllables

  • gray — gray1 [grā] adj. [ME grai < OE græg, akin to Ger grau < IE base * ĝher , to shine, gleam > Czech zříti, to see] 1. of a color that is a mixture or blend of black and white 2. a) darkish; dull b) dreary; dismal 3 …   English World dictionary

  • Gray — (gr[=a]), n. 1. A gray color; any mixture of white and black; also, a neutral or whitish tint. [1913 Webster] 2. An animal or thing of gray color, as a horse, a badger, or a kind of salmon. [1913 Webster] Woe worth the chase, woe worth the day.… …   The Collaborative International Dictionary of English


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