See more synonyms for domain on
  1. a field of action, thought, influence, etc.: the domain of science.
  2. the territory governed by a single ruler or government; realm.
  3. a realm or range of personal knowledge, responsibility, etc.
  4. a region characterized by a specific feature, type of growth or wildlife, etc.: We entered the domain of the pine trees.
  5. Law. land to which there is superior title and absolute ownership.
  6. Mathematics.
    1. the set of values assigned to the independent variables of a function.
    2. region(def 11a).
  7. Computers.
    1. a group of computers and devices on a network that are administered under the same protocol.
    2. the top level in a domain name, indicating the type of organization, geographical location, or both, and officially designated in the suffix, as .edu for institutions of higher education.
  8. Physics. one of many regions of magnetic polarity within a ferromagnetic body, each consisting of a number of atoms having a common polarity, and collectively determining the magnetic properties of the body by their arrangement.
  9. Crystallography. a connected region with uniform polarization in a twinned ferroelectric crystal.

Origin of domain

1595–1605; < French domaine, alteration, by association with Latin dominium dominium, of Old French demeine < Late Latin dominicum, noun use of neuter of Latin dominicus of a master, equivalent to domin(us) lord + -icus -ic
Related formsdo·ma·ni·al, adjective Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Examples from the Web for domain

Contemporary Examples of domain

Historical Examples of domain

  • His eyes glowed steadily as he contemplated this interloper in his domain.

    The Leopard Woman

    Stewart Edward White

  • They gave him the dukedom and domain of Bronte, worth about L3000 a year.

  • That part of eternity dividing the domain of disappointment from the realm of hope.

  • But this ordeal combat was far removed from the domain of sport.

    English Villages

    P. H. Ditchfield

  • There is thus no domain of the mind which is not influenced by love, and which does not react on love in its turn.

British Dictionary definitions for domain


  1. land governed by a ruler or government
  2. land owned by one person or family
  3. a field or scope of knowledge or activity
  4. a region having specific characteristics or containing certain types of plants or animals
  5. Australian and NZ a park or recreation reserve maintained by a public authority, often the government
  6. law the absolute ownership and right to dispose of landSee also demesne, eminent domain
  7. maths
    1. the set of values of the independent variable of a function for which the functional value existsthe domain of sin x is all real numbers Compare range (def. 8a)
    2. any open set containing at least one point
  8. logic another term for universe of discourse domain of quantification
  9. philosophy range of significance (esp in the phrase domain of definition)
  10. Also called: magnetic domain physics one of the regions in a ferromagnetic solid in which all the atoms have their magnetic moments aligned in the same direction
  11. computing a group of computers, functioning and administered as a unit, that are identified by sharing the same domain name on the internet
  12. Also called: superkingdom biology the highest level of classification of living organisms. Three domains are recognized: Archaea (see archaean), Bacteria (see bacteria), and Eukarya (see eukaryote)
  13. biochem a structurally compact portion of a protein molecule

Word Origin for domain

C17: from French domaine, from Latin dominium property, from dominus lord
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

Word Origin and History for domain

early 15c., in Scottish, from Middle French domaine "domain, estate," from Old French demaine "lord's estate," from Latin dominium "property, dominion," from dominus "lord, master, owner," from domus "house" (see domestic). Form influenced in Old French by Medieval Latin domanium "domain, estate." Internet domain name attested by 1985.

Online Etymology Dictionary, © 2010 Douglas Harper

domain in Medicine


  1. One of the homologous regions that make up an immunoglobulin's heavy and light chains and serve specific immunological functions.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.

domain in Science


  1. Mathematics The set of all values that an independent variable of a function can have. In the function y = 2x, the set of values that x (the independent variable) can have is the domain. Compare range.
  2. Computer Science A group of networked computers that share a common communications address.
  3. Biology A division of organisms that ranks above a kingdom in systems of classification that are based on shared similarities in DNA sequences rather than shared structural similarities. In these systems, there are three domains: the archaea, the bacteria, and the eukaryotes.
  4. Physics A region in a ferromagnetic substance in which the substance is magnetized with the same polarization throughout.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.