From Longman Dictionary of Contemporary Englishsourcesource1 /sɔːs $ sɔːrs/ ●●● S2 W1 AWL noun [countable] 1 COME FROM/ORIGINATEa thing, place, activity etc that you get something from They get their money from various sources.source of Beans are a very good source of protein. For me, music is a great source of enjoyment.at source British English Is your pension taxed at source (=before it is paid to you)?2 CAUSEthe cause of something, especially a problem, or the place where it startssource of We’ve found the source of the trouble. The recent name change has been the source of some confusion.3 TCNINFORMATIONa person, book, or document that supplies you with information List all your sources at the end of your essay. I’ve heard from reliable sources that the company is in trouble.4 SGthe place where a stream or river starts → mouth5 technical source codeCOLLOCATIONSADJECTIVES/NOUN + sourcea good/excellent/rich source (=a source that provides a lot of something)Milk is a good source of calcium.a useful sourcePeople said television was their most useful source of local information.a major/important sourceThe lead mines were once a major source of employment for the islanders.a great sourceIn times of stress, food can be a great source of comfort.the main/primary sourceIt started as a hobby, but now it is his main source of income.an alternative sourceThe university is exploring alternative funding sources.an energy sourceWe hope to see increased usage of renewable energy sources.a food sourceSlugs attack potatoes in late summer, when other food sources are disappearing.a power source (=something that produces power)First, you need to turn off the power source.a light source (=something that produces light)The statue is illuminated by a hidden light source.
Examples from the Corpussource• Take action immediately to rectify the problem at source.• Most Americans rely on television as their chief source of information.• The money comes from countless sources.• The sun is perhaps the least expensive energy source we have.• These discouraging factors combine to compel a search for cheaper and environmentally safer energy sources.• Beans and lentils are a very good source of protein.• In the case of an electric shock, turn the power off at its source.• Our source informed us that there was a possibility of another attack the following week, possibly in the central London area.• This is the largest recorded source of radioactive effluent in the world.• The tank's losing water, but we can't find the source of the leak.• Some Christians would say the Gospel is not the source or proof of what happened.• When they visited the Pipers' home they recognized the source of John's description in every detail.• The close correlation between the data obtained from these two sources suggests that recall error is unlikely to be a confounding factor.• The sound came from an unknown source, far away in the distance.• All of your sources have to be listed at the end of the paper.source of• Richard's learning disability was a source of embarrassment for him.• Milk is a very good source of calcium.• Money is often a major source of tension for married couples.• Her waitress job is the family's only source of income.reliable sources• There are few available and reliable sources.