\ˈsȯrs \

Definition of source 

(Entry 1 of 3)

1a : a generative force : cause

b(1) : a point of origin or procurement : beginning

(2) : one that initiates : author also : prototype, model

(3) : one that supplies information

2a : the point of origin of a stream of water : fountainhead

b archaic : spring, fount

3 : a firsthand document or primary reference work

4 : an electrode in a field-effect transistor that supplies the charge carriers for current flow — compare drain, gate


sourced; sourcing

Definition of source (Entry 2 of 3)

transitive verb

1 : to specify the source of (something, such as quoted material)

2 : to obtain from a source metals sourced from abroad



Definition of source (Entry 3 of 3)

: of, relating to, or being source code a source file

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Other Words from source


sourceless \ˈsȯrs-ləs \ adjective

Choose the Right Synonym for source


origin, source, inception, root mean the point at which something begins its course or existence. origin applies to the things or persons from which something is ultimately derived and often to the causes operating before the thing itself comes into being. an investigation into the origin of baseball source applies more often to the point where something springs into being. the source of the Nile the source of recurrent trouble inception stresses the beginning of something without implying causes. the business has been a success since its inception root suggests a first, ultimate, or fundamental source often not easily discerned. the real root of the violence

Examples of source in a Sentence


The college had its own power source. She has been a great source of strength to me. His job is the family's main source of income. A government source spoke to the press today. The reporter has refused to reveal his sources. According to one source, the program will not cost a lot. information from various intelligence sources
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Recent Examples on the Web: Noun

The Bucks didn’t rescind their $4.3 million qualifying offer to Jabari Parker before Friday’s late deadline, a source confirmed, which means the forward remains a restricted free agent. K.c. Johnson,, "Bulls working to sign restricted free agent Jabari Parker to offer sheet," 14 July 2018 In one case, a warden was forced to travel from Superior to Sheboygan to perform duties at Kohler-Andrea State Park, sources close to the department told the Milwaukee Journal Sentinel. Paul A. Smith, Milwaukee Journal Sentinel, "Wisconsin warden shortage and changes in responsibilities raise concerns," 14 July 2018 Professor Mukherjee says that photons from high-energy sources tend to get absorbed by infrared background radiation. Eoin O'carroll, The Christian Science Monitor, "Neutrino demonstration heralds a new way of observing the cosmos," 12 July 2018 Cued by IceCube, the Antarctic detector, the orbiting Fermi Gammaray Space Telescope found that the neutrino likely came from a far off blazar, a hugely bright source of radiation powered by a supermassive black hole. Daniel Clery, Science | AAAS, "Ghostly particle caught in polar ice ushers in new way to look at the universe," 12 July 2018 Kennedy did not report receiving income from his son on his financial disclosure forms from 2004 to 2016; these forms don't require him to list his adult children's income sources. Salvador Rizzo,, "There is an unfounded conspiracy theory about the Supreme Court and Trump Tower Chicago," 14 July 2018 Astronomers have traced a high-energy neutrino to its cosmic source for the first time ever, solving a century-old mystery in the process. Mike Wall, NBC News, "High-energy 'ghost particle' traced to distant galaxy in astronomy breakthrough," 12 July 2018 Even more exciting was such neutrinos had never before been traced to its source. Smithsonian, "Scientists Explain The Thrill of Detecting a Neutrino From a Far-Off Galaxy," 12 July 2018 Wing is working with the FAA and has made parts of its system open source, so others can make interoperable systems. Alex Davies, WIRED, "Inside X, the Moonshot Factory Racing to Build the Next Google," 11 July 2018

Recent Examples on the Web: Verb

As CEO of Sports Studios, based in Torrance, Calif., Koesterer is responsible for sourcing and outfitting all sports materials for a variety of movies, television shows and commercials. Jeremy Fuchs,, "A Tour of Sports Movie Memorabilia Heaven," 6 July 2018 But this category of diverse pours — sourced from a country whose winemaking reaches back to antiquity — offers so much more. Ellen Bhang,, "Set the table with these distinctive Greek wines," 2 July 2018 Once again the library, which had been painstakingly restored, even down to sourcing Mackintosh’s original nails from America, was gutted. The Economist, "A burnt-out case," 21 June 2018 Now the data is in, much of it sourced by WIRED through a series of public records requests. Mark Harris, WIRED, "The Bike Share War Is Shaking Up Seattle Like Nowhere Else," 14 June 2018 Other players have been sourced through a vast Moroccan grapevine of scouts in Belgium, Germany and Spain. Tariq Panja, New York Times, "In Morocco, an Imported Team for the World Cup," 5 June 2018 All ingredients are sourced from North America and Europe. Molly Kimball,, "2018 Eat Local Challenge: No need to go hardcore to dig in," 22 May 2018 The flowers are sourced from farms in Wisconsin, Illinois and Michigan as seasonally available. Sarah Hauer, Milwaukee Journal Sentinel, "These bouquets are made for Instagram and leading a craft flower movement," 15 May 2018 It's made from scratch with fresh ingredients, many of which are locally sourced. Jennie Key,, "Lots of options: West Siders have eat-out options and more are coming," 13 July 2018

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


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


1957, in the meaning defined at sense 1


1959, in the meaning defined above

History and Etymology for source


Middle English sours, from Anglo-French surse spring, source, from past participle of surdre to rise, spring forth, from Latin surgere — more at surge

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Statistics for source

Last Updated

13 Oct 2018

Look-up Popularity

Time Traveler for source

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

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More Definitions for source



English Language Learners Definition of source

: someone or something that provides what is wanted or needed

: the cause of something (such as a problem)

: a person, book, etc., that gives information


\ˈsȯrs \

Kids Definition of source

1 : a cause or starting point the source of a rumor

2 : the beginning of a stream of water the source of the Nile River

3 : someone or something that supplies information a reference source

4 : someone or something that provides what is needed a source of supplies a source of strength



Legal Definition of source 

1 : a point of origin the source of the conflict

2 : one that supplies information a journalist's source

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Comments on source

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