Properly, the spring or fountain from which a stream of water proceeds, or any collection of water within the earth or upon its surface, in which a stream originates. This is called also the head of the stream. We call the water of a spring, where it issues from the earth, the source of the stream or rivulet proceeding form it. We say also that springs have their sources in subterranean ponds, lakes or collections of water. We say also that a large river has is source in a lake. For example, the St. Lawrence has its source in the great lakes of America.

First cause; original; that which gives rise to any thing. Thus ambition, the love of power and of fame, have been the sources of half the calamities of nations. Intemperance is the source of innumerable evils to individuals.

The first producer; he or that which originates; as Greece the source of arts.