King James Bible Dictionary

Called by the Accadians id Idikla; i.e., "the river of Idikla", the third of the four rivers of Paradise (Genesis 2:14). Gesenius interprets the word as meaning "the rapid Tigris." The Tigris rises in the mountains of Armenia, 15 miles south of the source of the Euphrates, which, after pursuing a south-east course, it joins at Kurnah, about 50 miles above Bassorah. Its whole length is about 1,150 miles.

sharp voice; sound

Ancient name of the River Tigris.
Genesis 2:14; Daniel 10:4

(rapid), one of the rivers of Eden, the river which "goeth eastward to Assyria," (Genesis 2:14) and which Daniel calls "the great river," (Daniel 10:4) seems to have been rightly identified by the LXX. with the Tigris. Dekel is clearly an equivalent of Digla or Dighath, a name borne by the Tigris in all ages. The name now in use among the inhabitants of Mesopotamia is Dijleh .