do·​main | \ dō-ˈmān How to pronounce domain (audio) , də- \

Definition of domain

1 law
a : complete and absolute (see absolute sense 3) ownership of land our highways and roads have been in the domain of state and local governments— T. H. White b. 1915 — compare eminent domain
b : land so owned
2 : a territory over which dominion (see dominion sense 2) is exercised The forest is part of the king's domain.
3 : a region distinctively marked by some physical feature a domain of rushing streams, tall trees, and lakes
4 : a sphere (see sphere sense 4b) of knowledge, influence, or activity the domain of biblical scholarship outside the domain of city police
5 mathematics : the set of elements (see element sense 2b(3)) to which a mathematical or logical variable is limited specifically : the set on which a function (see function entry 1 sense 5a) is defined
6 physics : any of the small randomly oriented regions of uniform magnetization in a ferromagnetic substance
7 mathematics : integral domain
8 biology : the highest taxonomic category in biological classification ranking above the kingdom (see kingdom sense 4b)
9 biochemistry : any of the three-dimensional subunits of a protein that are formed by the folding of its linear peptide chain and that together make up its tertiary (see tertiary entry 1 sense 3c) structure
10 computers : a subdivision of the Internet consisting of computers or sites usually with a common purpose (such as providing commercial information) and denoted in Internet addresses by a unique abbreviation (such as com for commercial sites or gov for government sites) The domain ca is used for sites located in Canada. also : domain name Our domain is

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Examples of domain in a Sentence

The forest is part of the king's domain. My sister is the math expert in the family, but literature is my domain. Childcare is no longer solely a female domain.
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Recent Examples on the Web European blackface and American minstrelsy alike assume that performing blackness is a white birthright—that the stage is a white domain in which blacks are not allowed to tell their own stories, or even enjoy basic dignities. Ayanna Thompson, Smithsonian Magazine, "Blackface Is Older Than You Might Think," 29 Apr. 2021 Subscriptions to Squarespace, which can be purchased on a monthly or annual basis, come with different options, from a simple plan including a domain and a website to more advanced options that provide website analytics and merchandising software. Deniz Çam, Forbes, "Squarespace Founder Is A Billionaire Ahead Of Direct Listing," 20 Apr. 2021 Space is now crucial for military operations, not only for Global Positioning System navigation and communications but also as a strategic domain in its own right. Nadia Schadlow, WSJ, "A Good Battery Is the Best Defense Against a Military Assault," 30 Mar. 2021 Memory Mukabeta runs a car repair shop, a vocation traditionally viewed as a male domain. Farai Mutsaka, The Christian Science Monitor, "In Zimbabwe, female laborers don't let gender roles define them," 8 Mar. 2021 All indicate that the days of launching satellites into a friendly domain are gone. Abraham Mahshie, Washington Examiner, "Space Force chief makes case for ‘purpose built’ service," 25 Feb. 2021 The situation prompted some lawmakers to seek ways to allow the UK to make a finding of genocide—a domain that has generally been the purview of the United Nations rather than individual states. Annabelle Timsit, Quartz, "UK-China relations imploded in 2020—and things could get worse," 23 Dec. 2020 Similarly, 2012’s Diablo 3 is fundamentally the same game as 1996’s Diablo, a descent into a demon’s domain largely enjoyed as an excuse for plunder and weaponry that turns you into an even more efficient demon-slaying machine. Joshua Rivera, Wired, "Video Game Hell Isn’t Nearly Agonizing Enough," 22 Dec. 2020 If future space policy stays the course, culminating in a return to the moon sometime in the mid-2020s, the prospects for space as a domain of peace and prosperity are bright. Alexander William Salter, National Review, "Making a Point with Moon Rocks," 14 Dec. 2020

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'domain.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of domain

15th century, in the meaning defined at sense 1a

History and Etymology for domain

alteration of Middle English demayne, from Anglo-French demeine, from Latin dominium, from dominus — see dominate

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Time Traveler for domain

Time Traveler

The first known use of domain was in the 15th century

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Statistics for domain

Last Updated

11 May 2021

Cite this Entry

“Domain.” Dictionary, Merriam-Webster, Accessed 15 May. 2021.

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More Definitions for domain



English Language Learners Definition of domain

: the land that a ruler or a government controls
: an area of knowledge or activity
: a section of the Internet that is made up of computers or sites that are related in some way (such as by use or source)


do·​main | \ dō-ˈmān How to pronounce domain (audio) \

Kids Definition of domain

1 : land under the control of a ruler or a government
2 : a field of knowledge or activity the domain of science


do·​main | \ dō-ˈmān, də- How to pronounce domain (audio) \

Medical Definition of domain

1 : any of the three-dimensional subunits of a protein that together make up its tertiary structure, that are formed by folding its linear peptide chain, and that are variously considered to be the basic units of protein structure, function, and evolution immunoglobulin light chains have two domains and heavy chains have four or five domains, depending on classJournal of the American Medical Association
2 : the highest taxonomic category in biological classification ranking above the kingdom

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