|Easton's Bible Dictionary|
The name of a country (Zechariah 9:1) which cannot be identified. Rawlinson would identify it with Edessa. He mentions that in the Assyrian inscriptions it is recorded that "Shalmanezer III. made two expeditions, the first against Damascus B.C. 773, and the second against Hadrach B.C. 772; and again that Asshurdanin-il II. made expeditions against Hadrach in B.C. 765 and 755."
Int. Standard Bible Encyclopedia
ha'-drak, had'-rak (chadhrakh): "The land of Hadrach" is mentioned only once in Scripture (Zechariah 9:1), and there it is grouped with Damascus, Hamath, Tyre and Sidon. It may be safely identified with the "Hatarikka" of the Assyrian inscriptions, against which Assur-dan III made expeditions in his 1st (772 B.C.), 8th and 18th years. It also appears in inscriptions of Tiglath-pileser III. They place it in the North of Lebanon.
Hadrach (1 Occurrence)
Zechariah 9:1 An oracle. The word of Yahweh is against the land of Hadrach, and will rest upon Damascus; for the eye of man and of all the tribes of Israel is toward Yahweh; (WEB KJV JPS ASV BBE DBY WBS YLT NAS RSV NIV)