Albert Barnes Commentary 2 Kings 8:26

"Two and twenty years old was Ahaziah when he began to reign; and he reigned one year in Jerusalem. And his mother`s name was Athaliah the daughter of Omri king of Israel." — 2 Kings 8:26 (ASV)

Such names as Athaliah, Jehoram, and Ahaziah indicate that the Baal-worshipping kings of Israel did not openly renounce the service of Yahweh. Athaliah means “the time for Yahweh,” Ahaziah means “the possession of Yahweh,” and Jehoram, or Joram, means “exalted by Yahweh.”

The daughter of Omri - The terms “son” and “daughter” were used by the Jews for any descendant . The entire nation, for example, was called “the children of Israel.” Athaliah was actually Omri’s granddaughter. Her being called “the daughter of Omri” implies that a special greatness was associated with him, so that his name prevailed over that of Ahab. Indications of this special greatness are found in the Assyrian inscriptions, where the early name for Samaria is Beth-Omri, and where even Jehu is called “the son of Omri.”