Jehoram (meaning "exhalted" in Hebrew) was the name of several individuals in the Old Testament.
4. The son of Ahab and Jezebel, and successor to his brother Ahaziah as king of Israel. He reigned twelve years (2 Kings 1:17; 3:1), Albright dating his reign to 849 - 842 BC, while Thiele offers the dates of 852 - 841 BC. His first work was to reduce to subjection the Moabites, who had asserted their independence in the reign of his brother. Jehoshaphat, king of Judah, assisted Jehoram in this effort. He was further helped by his ally the king of Edom. Elisha went forth with the combined army (2 Kings 3:1-19), and at the solicitation of Jehoshaphat encouraged the army with the assurance from the Lord of a speedy victory. The Moabites under Mesha their king were utterly routed and their cities destroyed. At Kir-haraseth Mesha made a final stand. The Israelites refrained from pressing their victory further, and returned to their own land.
Elisha afterwards again befriended Jehoram when a war broke out between the Syrians and Israel, and in a remarkable way brought that war to a bloodless close (2 Kings 6:23). But Jehoram, becoming confident in his own power, sank into idolatry, and brought upon himself and his land another Syrian invasion, which led to great suffering and distress in Samaria (2 Kings 6:24-33). By a remarkable providential interposition the city was saved from utter destruction, and the Syrians were put to flight (2 Kings 7:6-15).
Jehoram was wounded in a battle with the Syrians at Ramah, and obliged to return to Jezreel (2 Kings 8:29; 9:14, 15), and soon after the army proclaimed their leader Jehu king of Israel, and revolted from their allegiance to Jehoram (2 Kings 9). Jehoram was pierced by an arrow from Jehu's bow on the piece of ground at Jezreel which Ahab had taken from Naboth, and there he died (2 Kings 9:21-29).
5. The eldest son and successor of Jehoshaphat, king of Judah. He reigned eight years alone as king of Judah, Albright dating his reign to 849 - 842 BC, while Thiele offers the dates of 848 - 842 BC. He had previously been associated with his father (2 Chr. 21:5, 20; 2 Kings 8:16) for some years. His wife was Athaliah, the daughter of Ahab and Jezebel. His daughter Jehosheba was married to the high priest Jehoiada. He sank into gross idolatry, and brought upon himself and his kingdom the anger of Jehovah. The Edomites revolted from under his yoke, and the Philistines and the Arabs and Cushites invaded the land, carrying away great spoil, along with Jehoram's wives and all his children, except Ahaziah. He died a painful death from a fearful malady, and was refused a place in the sepulchre of the kings (2 Kings 8:16-24; 2 Chr. 21).
Initial text from Easton's Bible Dictionary, 1897 -- Please update as needed