de·​fine | \di-ˈfīn \
defined; defining

Definition of define 

transitive verb

1a : to determine or identify the essential qualities or meaning of whatever defines us as human

b : to discover and set forth the meaning of (something, such as a word) how the dictionary defines "grotesque"

c computing : to create with established rules or parameters define a window define a procedure

2a : to fix or mark the limits of : demarcate rigidly defined property lines

b : to make distinct, clear, or detailed especially in outline the issues aren't too well defined eyes defined by mascara

3 : characterize, distinguish you define yourself by the choices you makeDenison Univ. Bull. the moment that defined the campaign

intransitive verb

: to make a definition (see definition sense 1a)

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Other Words from define

definement \ -​ˈfīn-​mənt \ noun
definer \ -​ˈfī-​nər \ noun

Synonyms for define


lay down, prescribe, specify

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Examples of define in a Sentence

a term that is difficult to define The government study seeks to define urban poverty. Her book aims to define acceptable social behavior. She believes that success should be defined in terms of health and happiness. That fence defines the far edge of the property.
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Recent Examples on the Web

Low-income families were defined as less than about $26,000. Eric Stirgus, ajc, "Study: More middle-income students squeezed from top colleges," 12 July 2018 For me, though, the weight of food and water is generally the defining limitation in my trips. Alex Hutchinson, Outside Online, "Here's What It Takes to Hike the John Muir Trail," 11 July 2018 Justice Kennedy’s presence on the court did not immunize the institution from these defining features. Chase Strangio, Teen Vogue, "The Supreme Court Has Long Been a Tool of Oppression," 3 July 2018 Ever since Margaret Thatcher ripped up the rule book for London’s financial markets in 1986, Tories have defined themselves as capitalism’s praetorian guard. Caroline Alexander,, "A Retirement, a Failed Coup and a Taboo: Weekend Reads," 30 June 2018 Dangerous Visions has been hailed as a defining touchstone of the New Wave movement. Andrew Liptak, The Verge, "Harlan Ellison, one of science fiction’s most controversial authors, has died," 28 June 2018 The decision follows a High Court ruling in December that the upkeep of the Netanyahus' personal property in Caesarea, which is defined as an official state residence, is a taxable benefit given to a public servant. Jewish Journal, "Bill to exempt Israeli prime ministers from certain taxes passes first reading," 26 June 2018 Because of its lack of civilization, the Antarctic is defined entirely by its geography. David Grossman, Popular Mechanics, "The Bedrock Below West Antarctica Is Rising Shockingly Fast," 25 June 2018 Yet a placenta very often ends up in medical waste without much thought given to its defining role in pregnancy. Tara Shafer, Redbook, "I Lost a Baby at 33 Weeks — Now I'm Fighting to Spare Others the Same Pain," 19 June 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'define.' 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 define

14th century, in the meaning defined at transitive sense 1a

History and Etymology for define

Middle English diffinen, defynen, borrowed from Anglo-French definer, diffiner, borrowed (with conjugation change) from Medieval Latin dēfīnīre, diffīnīre (dif- by association with dif-, assimilated form of dis- dis-), going back to Latin dēfīnīre "to mark the limits of, determine, give an exact description of," from dē- de- + fīnīre "to mark out the boundaries of, limit" — more at finish entry 1

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Statistics for define

Last Updated

5 Nov 2018

Look-up Popularity

Time Traveler for define

The first known use of define was in the 14th century

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More Definitions for define



English Language Learners Definition of define

: to explain the meaning of (a word, phrase, etc.)

: to show or describe (someone or something) clearly and completely

: to show the shape, outline, or edge of (something) very clearly


de·​fine | \di-ˈfīn \
defined; defining

Kids Definition of define

1 : to explain the meaning of define a word

2 : to make clear especially in outline Your responsibilities are defined in the handout.

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Comments on define

What made you want to look up define? Please tell us where you read or heard it (including the quote, if possible).


to clear from alleged fault or guilt

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