[ grey ]
See synonyms for gray on
adjective,gray·er, gray·est.
  1. of a color between white and black; having a neutral hue.

  2. dark, dismal, or gloomy: gray skies.

  1. dull, dreary, or monotonous.

  2. having gray hair; gray-headed.

  3. pertaining to old age; mature.

  4. Informal. pertaining to, involving, or composed of older persons: gray households.

  5. old or ancient.

  6. indeterminate and intermediate in character: The tax audit concentrated on deductions in the gray area between purely personal and purely business expenses.

  1. any achromatic color; any color with zero chroma, intermediate between white and black.

  2. something of this color.

  1. gray material or clothing: to dress in gray.

  2. an unbleached and undyed condition.

  3. (often initial capital letter) a member of the Confederate army in the American Civil War or the army itself.: Compare blue (def. 5).

  4. a horse of a gray color.

  5. a horse that appears white but is not an albino.

verb (used with or without object)
  1. to make or become gray.

Origin of gray

First recorded before 900; Middle English grei, grai, Old English grǣg, grēg; cognate with German grau, Old Norse grār
  • Also especially British, grey .

Other words from gray

  • grayly; especially British, greyly, adverb
  • grayness; especially British, greyness, noun
  • un·grayed; especially British, un·greyed, adjective

Other definitions for gray (2 of 3)

[ grey ]

  1. the standard unit of absorbed dose of radiation (such as x-rays) in the International System of Units (SI), equal to the amount of ionizing radiation absorbed when the energy imparted to matter is 1 J/kg (one joule per kilogram). Abbreviation: Gy

Origin of gray

First recorded in 1975; named in honor of Louis Harold Gray (1905–65), English radiobiologist

Other definitions for Gray (3 of 3)

[ grey ]

  1. A·sa [ey-suh], /ˈeɪ sə/, 1810–88, U.S. botanist.

  2. Robert, 1755–1806, U.S. explorer and sea captain: discovered the Columbia River.

  1. Thomas, 1716–71, English poet. Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use gray in a sentence

British Dictionary definitions for gray (1 of 3)


/ (ɡreɪ) /

adjective, noun, verb
  1. a variant spelling (now esp US) of grey

Derived forms of gray

  • grayish, adjective
  • grayly, adverb
  • grayness, noun

British Dictionary definitions for gray (2 of 3)


/ (ɡreɪ) /

  1. the derived SI unit of absorbed ionizing radiation dose or kerma equivalent to an absorption per unit mass of one joule per kilogram of irradiated material. 1 gray is equivalent to 100 rads: Symbol: Gy

Origin of gray

C20: named after Louis Harold Gray (1905–65), English physicist

British Dictionary definitions for Gray (3 of 3)


/ (ɡreɪ) /

  1. Thomas. 1716–71, English poet, best known for his Elegy written in a Country Churchyard (1751)

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Scientific definitions for gray


[ grā ]

  1. The SI derived unit used to measure the energy absorbed by a substance per unit weight of the substance when exposed to radiation. One gray is equal to one joule per kilogram, or 100 rads. The gray is named after British physicist Louis Harold Gray (1905-1965).

The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

Other Idioms and Phrases with gray


In addition to the idioms beginning with gray

  • gray area
  • gray matter

also see:

  • get gray hair from

The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.