Euphrates

Boyd’s Bible Dictionary:

(fructifying). A great river of western Asia, rising in Armenia and emptying into the Persian Gulf. Boundary of Eden (Gen. 2:14); “great river” (Gen. 15:18; Deut. 1:7); eastern boundary of the promised land (Deut. 11:24; Josh. 1:4; 1 Chron. 5:9); and of David’s conquests (2 Sam. 8:3; 1 Chron. 18:3. See also, {vi 19271-19274;20048-20056;20276}Jer. 13:4-7; 46:2-10; 51:63; Psa. 137:1; {vi 30855;30967}Rev. 9:14; 16:12).

Concise Bible Dictionary:

Euphrates from the air.
This river is first mentioned in connection with the garden of Eden, but cannot be thereby traced (Gen. 2:14). It was the N.E. boundary of the land promised to Abraham, as the river of Egypt was the S.W. (Gen. 15:18). It is called the great river, the river Euphrates (Deut. 1:7), and at times is merely called “the river” (Gen. 31:21). David was able to possess the land to the Euphrates (2 Sam. 8:3), which also Solomon maintained (1 Kings 4:24).
In one of Jeremiah’s typical actions he hid his girdle by the Euphrates: then found it spoiled and useless; so should the pride of Judah and Jerusalem be marred ({vi 19271-19278}Jer. 13:4-11)—a figure of the carrying away to Babylon of those who should have cleaved to the Lord for His praise, as a girdle to the loins of a man. The prophecy against Babylon was written by Jeremiah in a book, and given to Seraiah, who was to read the same when he arrived at Babylon, then tie a stone to the book and cast it into the Euphrates, and say “Thus shall Babylon sink” ({vi 20272-20277}Jer. 51:59-64). The book was thus placed in the river in which the Babylonians trusted for safety, but which was the channel of their destruction (Isa. 45:1).
The Euphrates is mentioned in the Revelation as the place where four angels are or will be bound, who will be loosed at the sixth trumpet, letting loose the Eastern forms of Satanic wickedness, which has up to now been held in check (Rev. 9:14). Viewing Palestine as the center of God’s dealings with the earth, the Euphrates was the barrier between East and West. The sixth vial will be poured upon the great river Euphrates, that it may be dried up and a way be made for the kings from the East to come unto the great battle of Armageddon (Rev. 16:12).
There are two sources of the river; one in the Armenian mountains, about 40° N, 41° 30' E, and the other in the mountain range of Ararat, about 39° 30' N, 43° E. When the streams join they run nearly south and then south east for 1000 miles. After being joined by the Tigris it falls into the Persian Gulf. It is generally supposed that the river has not always in all parts run in the same channel; that after overflowing its banks it has not always returned to its former course, though it ran into it again farther south. A glance at a map will show that the possessions of David could have embraced but a very small part of the Euphrates, about Lat. 35° to 36° N. The great Syrian desert of Arabia separated the southern part of the river from Palestine.
River scenes on the Euphrates – taken at Hilla.

Strong’s Dictionary of Greek Words:

Number:
2166 (find all occurrences in KJV Bible)
Greek:
Εὐφράτης
Transliteration:
Euphrates
Phonic:
yoo-frat’-ace
Meaning:
of foreign origin (compare 6578); Euphrates, a river of Asia
KJV Usage:
Euphrates

Jackson’s Dictionary of Scripture Proper Names:

fruitfulness

Potts’ Bible Proper Names:

Flowing of waters; outpouring; to break forth; unlimited:―river of western Asia, Rev. 9:14. {Inundatio aquae}