source

noun

• 1a place, person, or thing from which something originates or can be obtained:mackerel is a good source of fish oil
• a spring or fountain head from which a river or stream issues:the source of the Nile
• a person who provides information:military sources announced a reduction in strategic nuclear weapons
• a book or document used to provide evidence in research: a historian will need to use both primary and secondary sources

• 2 technical a body or process by which energy or a particular component enters a system: major sources and sinks exist for atmospheric oxygenThe opposite of sink².
• Electronics a part of a field-effect transistor from which carriers flow into the inter-electrode channel.

verb

• obtain from a particular source:each type of coffee is sourced from one country
• find out where (something) can be obtained:she was called upon to source a supply of carpet