Definition of source in US English:



  • 1A place, person, or thing from which something comes or can be obtained.

    ‘mackerel is a good source of fish oil’
    • ‘Mercury concentrates in large fish at the top of the food chain, but these fish are not used as the source of most fish oil.’
    • ‘Extracting water from its sources originally required considerable effort.’
    • ‘These swimmers could form a trust or charity making it easier to obtain money from other sources and to receive a grant from the council.’
    • ‘The villagers were not consulted, even though the river was their only source of water and they depended on the sago trees for food.’
    • ‘Fish is a key source of omega 3 oils which have health benefits particularly for the heart.’
    • ‘Advances in physics and engineering are making energy from renewable sources increasingly affordable.’
    • ‘Glucose is the principal circulating sugar in the blood and the major energy source of the body.’
    • ‘The chief sources of phosphorus in river water are the weathering of rocks and the leaching out of fertilizers from agricultural land.’
    • ‘The sun is a powerful source of electromagnetic energy.’
    • ‘Well, many of the foods you eat contain carbohydrates, which are used by your body as a source of energy.’
    • ‘The cleanest energy sources of electricity are solar panels and wind turbines, which are only starting to be used in Canada.’
    • ‘It is not right for a physician to turn a research patient into a source of personal profit.’
    • ‘Best results will be obtained when two protein sources are used in combination.’
    • ‘Each of the millions of cars in the United States is potentially a source of air pollution.’
    • ‘There was a time long ago when books provided the main source of entertainment.’
    • ‘Seeds were obtained from various sources and greenhouse grown.’
    • ‘We will be more prosperous and more secure when we are less dependent on foreign sources of energy.’
    • ‘These products are obtained from fairly traded sources, where producers are paid a fair price that covers production costs and a basic living wage.’
    • ‘Church and civil records are also a great source for those researching the family tree.’
    • ‘Stem cells can be obtained from alternative sources, such as adult bone marrow.’
    origin, place of origin
    View synonyms
    1. 1.1 A spring or fountainhead from which a river or stream issues.
      ‘the source of the Nile’
      • ‘We proceeded down a windy country road, following the River Chew towards its source.’
      • ‘This spring is situated at the foot of the Banibal pass in the Pir Panjal range in Kashmir, and is said to be the source of the Jhelum River.’
      • ‘The terrace is watered by one of the sources of the River Jordan, a spring from a cool cave.’
      • ‘The source of the river was over 8km away as the crow flies, and we had come prepared for a long trip.’
      • ‘The pond is one of the sources of Shakujii River and used to be a place of annual pilgrimage for the rice-farmers living along its banks.’
      • ‘The track follows the river to its source, traverses the Southern Alps and ends on the West Coast, south of Karamea.’
      • ‘He added that he had not been aware that so many rivers had their source on Drehid bog.’
      • ‘Lying at the head of the beautiful Eden Valley, the source of the River Eden can be found in the Mallerstang Valley to the south east of the town.’
      • ‘The quest for the source of the Niger river and the location of the fabled central African city of Timbuctoo were among their central preoccupations.’
      • ‘The trip back to the main highway follows the Buller River from its source at Lake Rotoiti to Kawatiri Junction.’
      • ‘Kenya shares Lake Victoria, the largest lake in Africa and the main source of the Nile River, with Tanzania and Uganda.’
      • ‘It led him to give up his business and embark on a series of perilous journeys into the heart of equatorial Africa to find the true source of that mighty river.’
      • ‘He was also convinced that this lake contained the source of the River Nile, for which explorers had been searching for years.’
      • ‘We could follow the entire sweep of the river, from the lower meanders upwards to the source of the tiny stream high in the glaciated peaks of the cordillera.’
      • ‘Neither the source of the Missouri River nor the Shoshones had been found.’
      • ‘They come from places far and wide to worship their ancestors at the source of the Ethiope River in Southern Nigeria.’
      • ‘Four days up the Amazon from the ocean, and more than another four days from the Andes where that river has its sources, lies the town of Manaus.’
      • ‘Johannesburg may not be built on a river or harbour, but its streams are the source of two of southern Africa's mightiest rivers.’
      • ‘They have issued a five-point plan for managing rivers from source to estuary in an integrated and sustainable way.’
      • ‘The source of the river is a small dam in the Willem Conradie Park in Florida Hills.’
      spring, origin, head, well head, headspring, headwater, headwaters
      View synonyms
    2. 1.2 A person who provides information.
      ‘military sources announced a reduction in strategic nuclear weapons’
      • ‘However, informed sources point out that any such individual arrangement with a firm would be regarded as a serious breach of the rules and could not be ignored.’
      • ‘It was also alleged that he had been asked to provide information from police sources by senior activists.’
      • ‘After his death, the BBC announced that he was the sole source of information in the report.’
      • ‘It's also new territory for me to call up my former colleagues/friends as a reporter to interview them as sources with information about the lay-offs.’
      • ‘The anonymous sources provided information as opposed to opinion.’
      • ‘He rejected the proposal on the ground that such an important decision should not be governed by personal ambitions but by economic factors, informed sources say.’
      • ‘Informed sources said the financier has been sounded out to provide financial backing for a new bid.’
      • ‘Any information from our sources on that possibility and the fears U.S. officials obviously have about that possibility?’
      • ‘He also revealed sources had informed him two small attack jets had been flying together rather than the lone fighter indicated by earlier reports.’
      • ‘Beaver, who says he was passed the information by reliable military sources, says the equipment simply did not arrive in time.’
      • ‘Clinic staff may be seen as authoritative sources of prevention information.’
      • ‘Informed sources, however, say it appears clear that the Commonwealth does have the power to subsume the state industrial relation systems.’
      • ‘He insists we were given no information by a Crown source other than its press officer, who did not provide the quotes in our article.’
      • ‘I had no reason to doubt the accuracy of the story or the information provided by my sources.’
      • ‘A major housing and retail development complex is in the pipeline for the north of Carlow Town, informed sources told the paper this week.’
      • ‘A retired FBI agent was one of the authors' best sources of information.’
      • ‘Anonymous Egyptian police sources released information that they were seeking nine Pakistani suspects but this lead proved spurious.’
      • ‘He also sent collaborators to the South in an attempt to obtain military information, the sources said.’
      • ‘Also, why, and on whose authority, did unnamed police sources leak information to the press?’
      • ‘Youth identified parents, friends and school as their most important sources of information on post-secondary education.’
      reference, authority, informant
      View synonyms
    3. 1.3 A book or document used to provide evidence in research.
      • ‘Very occasionally there are links between documentary sources and the archaeological record.’
      • ‘The acute dearth of primary sources or written documents left by the servants themselves in the colonial period acts as a stumbling block.’
      • ‘These estimates are based on a massive and meticulous use of primary and secondary sources that are well documented in the volume.’
      • ‘While researching a book, Barker goes straight to primary sources, favouring public records, diaries, letters.’
      • ‘I used the book as my primary source and then I spent a lot of time observing women.’
      • ‘Though Benton has done research in Spanish primary sources, most of the book is based on secondary material.’
      • ‘History is based on evidence, sources and research.’
      • ‘One of the books was a primary source on early Christian literature.’
      • ‘The book relies both on original research based on primary sources and on an impressive list of secondary sources.’
      • ‘Talbot has researched his subject masterfully, combining primary and secondary sources with great skill.’
      • ‘His work draws upon archival documents, published sources, and legal cases.’
      • ‘A new emphasis will be placed on using primary documents as the source for research and discussion.’
      • ‘Written sources provide evidence of wall paintings in synagogues from medieval times, and the wooden synagogues of eastern Europe were richly decorated.’
      • ‘Finally, the book lists 3,000 other sources if you need further information.’
      • ‘This well-referenced book cites many quality sources and meaningful research.’
      • ‘It is based on sound research in archival and secondary sources.’
      • ‘The research is solidly based in published primary sources: books, pamphlets, and trial records.’
      • ‘Entirely secondary, Topsell's research relies on sources like Aristotle, Pliny, Plutarch, and Strabo to build its account.’
      • ‘There are no citations, and the bibliography lists but 14 secondary and four primary sources.’
      • ‘My friends always turned to me for help in figuring out how to document their sources for high school research papers.’
      reference, authority, informant
      View synonyms
    4. 1.4technical A body or process by which energy or a particular component enters a system.
      The opposite of sink
    5. 1.5Electronics A part of a field-effect transistor from which carriers flow into the inter-electrode channel.
      • ‘In one embodiment, the output of the buffer is at the source of the input transistor.’


[with object]
  • 1Obtain from a particular source.

    ‘each type of coffee is sourced from one country’
    • ‘They have been sourced from a wide range of brewers across Britain.’
    • ‘The spirit itself will continue to be sourced from the Caribbean.’
    • ‘Tony hopes the number of organic farms will increase so that more ingredients can be sourced here.’
    • ‘The vineyard is planted in Bordeaux red varietals with Sauvignon Blanc being sourced from Marlborough.’
    • ‘Medication had to be sourced from district health facilities, private nursing homes and pharmacies for newborns.’
    • ‘All purchased forage and bedding should be sourced from suppliers operating to recognised quality control standards.’
    • ‘Some of the food is being sourced from traders who attend the farmers' market.’
    • ‘As much of the menu as possible is sourced locally, which means there is an emphasis on seafood and fish.’
    • ‘Right here in Hanoi we have all the fish and chips we could eat and I've even managed to source a pretty decent bangers and mash.’
    • ‘Many villagers feel aggrieved that water is sourced from rural areas to supply towns but the rural infrastructure has to go without.’
    • ‘Still, once money has been sourced, a writer can be employed.’
    • ‘They feel let down by the yearly assurances that water for Tullamore households will be sourced from elsewhere.’
    • ‘The shop sources some of its most sought after items from remote villages across the South.’
    • ‘Currently, the county's gas supply is sourced from the North Sea.’
    • ‘The serrano was excellent, slightly thicker and much dryer than prosciutto; Tapeo had sourced a really good ham.’
    • ‘Building stone and roof tiles have to conform to rigid specifications, and must be locally sourced.’
    • ‘The mill in Portlaoise closed around that time and cloth had to be sourced elsewhere.’
    • ‘Mr Boland said the cost of the implementation of the scheme would be sourced from the pay parking income.’
    • ‘At the moment, lamb is being sourced locally.’
    • ‘Sausages and burgers have been sourced from local producers.’
    1. 1.1 Find out where (something) can be obtained.
      ‘she was called upon to source a supply of carpet’
      • ‘Many reclaimed cast iron radiators come without valves, therefore the correct ones have to be sourced, which can prove problematic.’
      • ‘The task was basically a treasure hunt for a list of items to be sourced and purchased for the lowest possible price ranging from a bottle of champagne to a bowler hat.’
      • ‘This saved me the trouble of having to source components to squeeze into the case, allowing me to simply customise what we needed.’
      • ‘The challenge now is to continue sourcing the right calibre of employee so that the business can develop and deliver on its expansion plans.’
      • ‘The service ranges from sourcing reliable cleaners, gardeners or plumbers to helping with house moves or booking a holiday.’
      • ‘It would be a great help if they could source a regular supply.’
      • ‘The difficulty in sourcing timbers led him to open a recycled timber business.’
      • ‘There was one famous incident where he was asked for a particular type of doll and he had dreadful trouble sourcing it.’
      • ‘Laois County Council is currently sourcing a suitable alternative site for the Fire Station.’
      • ‘Any help in sourcing suitable grounds in the general Ballyhaunis area would be greatly appreciated.’
      • ‘Ruth's main job in the preparation of the garden is sourcing plants which will be used in the display which will be seen by the many thousands of visitors to the annual event.’
      • ‘The company's buyers were responsible for sourcing the raw materials.’
      • ‘At one end of the spectrum is the provision of a children's playground and at the other sourcing a site for a new burial ground.’
      • ‘Newsgroups are one of the least expensive and most efficient ways to source information about Papua from the internet.’
      • ‘I know for a fact that even the private sector is having difficulties sourcing pharmacists locally.’
      • ‘Many small, rural schools are also having problems sourcing qualified staff.’
      • ‘They all have complex supply chains, sourcing materials from across the industry and making them vulnerable to the big drug companies.’
      • ‘I've also been trying to source Ammonium Ferric Sulphate and Copper Sulphate, for electro etching.’
      • ‘I use my e-mail nearly as much as the phone now and I find the internet a great tool for sourcing information for our shows.’
      • ‘Moira McCauley has travelled around the Scottish islands sourcing abandoned homes for a strangely chilling exhibition.’


  • at source

    • 1At the point of origin or issue.

      ‘reduction of pollution at source’
      • ‘According to Beggan, the secret is to do your quality control at source.’
      • ‘The more compassionately we treat illegal arrivals who are purely economic migrants the more harm we do to their countries of origin, and the more we help perpetuate the poverty at source.’
      • ‘The phrase ‘high level’ is a way of describing the objective in the first recital, which is to prevent or reduce to the irreducible minimum the emission of pollutants at source.’
      • ‘This issue is particularly important in kitchens and bathrooms, and O'Rourke says extracting moisture at source using extractor fans will cut down on lingering smells as well as preventing dampness.’
      • ‘While industrial pollution can be controlled at source, automobile emissions can become uncontrollable.’
      • ‘By preventing pollution at source, conserving water and restoring valuable nutrients to nature's lifecycle, the WCT's virtues are attracting converts around the world.’
      • ‘Noise, smell and other forms of pollution must be reduced to a minimum at source - if it is practical eliminate it.’
      • ‘The long-term health risks of placing fluoride into drinking water at source is to be raised at tomorrow's meeting of Kerry county council.’
      • ‘They represent the strongest indication of the growing international emphasis on waste disposal at source and the adoption of a precautionary approach to pollution control.’
      • ‘The reduction of refuse at source is vital and the council must challenge those responsible to achieve acceptable levels.’
      1. 1.1Used to show that an amount is deducted from earnings or other payments before they are made.
        ‘your pension contribution will be deducted at source’
        • ‘These enable you to access a multitude of offshore funds in an administratively simple and cost-effective manner - and with no tax deducted at source.’
        • ‘However, anyone with benefits or other sources of income, for example bank interest or dividend income, is likely to have additional tax to pay as any tax deducted at source is unlikely to cover the full tax liability.’
        • ‘Mortgage interest relief has gone and non-taxpayers can no longer reclaim the tax deducted at source on dividend payments on shares or unit trusts.’
        • ‘The bank has urged the public and corporate bodies to avail of the services for remitting their corporate, income, wealth and other direct taxes including tax deducted at source.’
        • ‘My mother's income is just below her tax allowance but she has some money in shares and unit trusts where tax on the income is deducted at source and cannot be reclaimed.’
        • ‘These repayments do not include mortgage interest tax relief which, from January 1, will be deducted at source from your repayment by the lender.’
        • ‘The landlord is then entitled to claim a credit for the income tax deducted at source from the rental income.’
        • ‘The onshore bond invests into onshore funds, which have tax deducted at source.’
        • ‘Meanwhile charges and commissions continue to be deducted at source, adding to investors' losses.’
        • ‘One piece of good news is that the majority of Britons do not need to complete a tax return, as all of their income (wages, savings interest and share dividends) is taxed at source.’


Late Middle English: from Old French sours(e), past participle of sourdre ‘to rise’, from Latin surgere.