What does 2 Kings 9:14 mean?

Jehu, son of Jehoshaphat and grandson of Nimshi, decided to go against King Joram. At the time, Joram was defending Ramoth-gilead from King Hazael of Aram, but he’d gone back to Jezreel to recover from his wounds. 2 Kings 9:14 - Modern Text Bible

(Jehu, a military commander, chooses to rebel against the current king, Joram, who is away from the battlefield due to injuries.)