from The American Heritage® Dictionary of the English Language, 5th Edition.

  • noun A territory over which rule or control is exercised.
  • noun A sphere of activity, influence, or knowledge: synonym: field.
  • noun The set of all possible values of an independent variable of a function.
  • noun An open connected set that contains at least one point.
  • noun Computers A group of networked computers that share a common communications address.
  • noun Physics Any of numerous contiguous regions in a ferromagnetic material in which the direction of spontaneous magnetization is uniform and different from that in neighboring regions.
  • noun Biology Any of three primary divisions of organisms, consisting of the eukaryotes, bacteria, and archaea, that rank above a kingdom in taxonomic systems based on similarities of DNA sequences.
  • noun Law The land of one with paramount title and absolute ownership.

from The Century Dictionary.

  • noun In mathematics: A set of numbers when the sums, differences, products, and quotients of any numbers in the set (excluding only the quotients of division by 0) always yield as results numbers belonging to the set.
  • noun The space within which a given function is developable in a series in powers of z–a: termed the domain of the point, z = adjective
  • noun In function-theory, the region of the z-plane within a circle about a as center with any radius less than the distance from a to the nearest critical point: called the domain of its center a.
  • noun Dominion; province of action; range or extent of authority: as, to trench on one's domain by interference.
  • noun The territory over which dominion is exercised; the territory ruled over by a sovereign, or under the government of a commonwealth: as, the domains of Great Britain.
  • noun An estate in land; landed property.
  • noun The land about the mansion-house of a lord, and in his immediate occupancy.
  • noun In law, ownership of land; immediate or absolute ownership; permanent or ultimate ownership. In the last two senses the word coincides with demain, demesne.
  • noun The range or limits of any department of knowledge or sphere of action, or the scope of any particular subject: as, the domain of religion, science, art, letters, agriculture, commerce, etc.; the judicial domain.
  • noun In logic, the breadth, extension, circuit, or sphere of a notion.
  • noun In the United States, the lands owned by the federal government or by a State; the public lands held for sale or reserved for specific uses.

from the GNU version of the Collaborative International Dictionary of English.

  • noun Dominion; empire; authority.
  • noun The territory over which dominion or authority is exerted; the possessions of a sovereign or commonwealth, or the like. Also used figuratively.
  • noun Landed property; estate; especially, the land about the mansion house of a lord, and in his immediate occupancy; demesne.
  • noun (Law) Ownership of land; an estate or patrimony which one has in his own right; absolute proprietorship; paramount or sovereign ownership.
  • noun (Math.) the set of values which the independent variable of a function may take. Contrasted to range, which is the set of values taken by the dependent variable.
  • noun (Math.) a connected set of points, also called a region.
  • noun (Physics) a region within a ferromagnetic material, composed of a number of atoms whose magnetic poles are pointed in the same direction, and which may move together in a coordinated manner when disturbed, as by heating. The direction of polarity of adjacent domains may be different, but may be aligned by a strong external magnetic field.
  • noun (Computers) an address within the internet computer network, which may be a single computer, a network of computers, or one of a number of accounts on a multiuser computer. The domain specifies the location (host computer) to which communications on the internet are directed. Each domain has a corresponding 32-bit number usually represented by four numbers separated by periods, as Each domain may also have an alphabetical name, usually composed of a name plus an extension separated by a period, as; the alphabetical name is referred to as a domain name.
  • noun (Immunology) the three-dimensional structure within an immunoglobulin which is formed by one of the homology regions of a heavy or light chain.
  • noun the field of knowledge, expertise, or interest of a person.
  • noun a particular environment or walk of life.
  • noun people in general; especially a distinctive group of people with some shared interest.
  • noun [U.S.] the situation or status of intellectual property which is not protected by copyright, patent or other restriction on use. Anything in the public domain may be used by anyone without restriction. The effective term of force of copyrights and patents are limited by statute, and after the term expires, the writings and inventions thus protected go into the public domain and are free for use by all.
  • noun that superior dominion of the sovereign power over all the property within the state, including that previously granted by itself, which authorizes it to appropriate any part thereof to a necessary public use, reasonable compensation being made.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

  • noun A geographic area owned or controlled by a single person or organization.
  • noun A sphere of influence.
  • noun A group of related items, topics, or subjects.
  • noun mathematics The set of all possible mathematical entities (points) where a given function is defined.
  • noun mathematics, topology, analysis An open and connected set in some topology. For example, the interval (0,1) as a subset of the real numbers.
  • noun computing, Internet Any DNS domain name, particularly one which has been delegated and has become representative of the delegated domain name and its subdomains
  • noun computing, Internet A collection of DNS or DNS-like domain names consisting of a delegated domain name and all its subdomains
  • noun computing A collection of information having to do with a domain, the computers named in the domain, and the network on which the computers named in the domain reside
  • noun computing The collection of computers identified by a domain's domain names
  • noun computing A small magnetized area of a bubble memory storing one bit, a bubble.
  • noun biology, taxonomy In the three-domain system, the highest rank in the classification of organisms, above kingdom; in other taxonomic systems, a similarly high rank
  • noun biology, taxonomy In the three-domain system, one of three taxa at that rank: Bacteria, Archaea, or Eukaryota.
  • noun biochemistry A folded section of a protein molecule that has a discrete function

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

  • noun territory over which rule or control is exercised
  • noun the content of a particular field of knowledge
  • noun people in general; especially a distinctive group of people with some shared interest


from The American Heritage® Dictionary of the English Language, 4th Edition

[French domaine, blend of Old French demaine (from Late Latin dominicum) and Latin dominium, property, both from dominus, lord; see dem- in Indo-European roots.]

from Wiktionary, Creative Commons Attribution/Share-Alike License

From Middle English demeine, demain ("rule"), Old French demeine, demaine, demeigne, domaine ("power"), (French domaine), from Latin dominium ("property, right of ownership"), from dominus ("master, proprietor, owner"). See dame, and confer demain, danger, dungeon.


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