source

The person, place or thing from which something (information, goods, etc.) comes or is acquired.

“The accused refused to reveal the source of the illegal drugs she was selling.”

Spring; fountainhead; wellhead; any collection of water on or under the surface of the ground in which a stream originates.

“The main sources of the Euphrates River are the Karasu and Murat Rivers.”

A reporter's informant.

Source code.

The name of one terminal of a field effect transistor (FET).

To obtain or procure: used especially of a business resource.

To find information about (a quotation)'s source (from which it comes): to find a citation for.