—n.
1 a spring or fountain-head from which a stream issues (the sources of the Nile).
2 a place, person, or thing from which something originates (the source of all our troubles).
3 a person or document etc. providing evidence (reliable sources of information; historical source material).
4 a a body emitting radiation etc. b Physics a place from which a fluid or current flows. c Electronics a part of a transistor from which carriers flow into the interelectrode channel.
—v.tr. obtain (esp. components) from a specified source.
Phrases and idioms:
at source at the point of origin or issue. source-criticism the evaluation of different, esp. successive, literary or historical sources.
Etymology: ME f. OF sors, sourse, past part. of sourdre rise f. L surgere
Useful english dictionary. 2012.