Easton's Bible Dictionary: M. G. Easton, M.A., D.D.
Hebrew, Perath; Assyrian, Purat; Persian cuneiform, Ufratush, whence Greek Euphrates, meaning "sweet water." The Assyrian name means "the stream," or "the great stream." It is generally called in the Bible simply "the river" (Ex. 23:31), or "the great river" (Dt. 1:7).
The Euphrates is first mentioned in Gen. 2:14 as one of the rivers of Paradise. It is next mentioned in connection with the covenant which God entered into with Abraham (15:18), when he promised to his descendants the land from the river of Egypt to the river Euphrates (comp. Dt. 11:24; Josh. 1:4), a covenant promise afterwards fulfilled in the extended conquests of David (2 Sam. 8:2-14; 1 Chr. 18:3; 1 Ki. 4:24). It was then the boundary of the kingdom to the north-east. In the ancient history of Assyria, and Babylon, and Egypt many events are recorded in which mention is made of the "great river." Just as the Nile represented in prophecy the power of Egypt, so the Euphrates represented the Assyrian power (Isa. 8:7; Jer. 2:18).
It is by far the largest and most important of all the rivers of Western Asia. From its source in the Armenian mountains to the Persian Gulf, into which it empties itself, it has a course of about 1, 700 miles. It has two sources,