Boyd’s Bible Dictionary:

(Jehovah sustains). Son of Ahab, and his successor on the throne of Israel, as the eighth king. Reign 896-895 B. C. A weak and foolish idolater (1 Kings 22:49-53). (2) Fifth king of Judah. Reign, B. C. 884 (2 Kings 8:25-29). Killed in the rebellion of Jehu (2 Kings 9). Called Azariah (2 Chron. 22:6); and Jehoahaz (2 Chron. 21:17).

Concise Bible Dictionary:

1. Son of Ahab and Jezebel. He reigned over Israel two years (B.C. 837-6) and did that which was evil in the sight of the Lord, it being remarked of him that he walked in the way of his mother as well as of his father and of Jeroboam. He was a worshipper of Baal; and having injured himself by falling through a lattice he sent to inquire of Baal-zebub, the god of Ekron. Elijah met the messengers on their road, and turned them back with a message to Ahaziah, reproaching him with his impiety, and telling him he should not recover from his sickness. Ahaziah, on finding by the description the messengers gave that it was Elijah, sent a captain and fifty men to seize him. Elijah called down fire from heaven and they were consumed. Another fifty were sent and they also were consumed. The captain of the third fifty begged Elijah to spare their lives, which he did, and he went with them and delivered the message to Ahaziah. The prediction was verified and he died. The history of this king presents a sad picture of the state of idolatry and wickedness into which Israel had fallen, while professing to be God’s people (1 Kings 22:49, 51-53; 2 Kings 1:1-18; 2 Chron. 20:35).
2. Son of Jehoram and Athaliah, daughter of Ahab and Jezebel, therefore nephew of the above. He succeeded his father as king of Judah, and reigned one year (B.C. 885). He did wickedly, his mother being his counseller to his destruction. He formed an alliance with Joram king of Israel and went with him against Hazael king of Syria. Joram was wounded and went to Jezreel to be healed. Ahaziah afterward went to visit Joram, and God caused his death by Jehu when he cut off the house of Ahab (2 Kings 8:24-29; 2 Kings 9:16-29; 2 Chron. 22:1-9). He is called AZARIAH in 2 Chronicles 22:6, and JEHOAHAZ in 2 Chronicles 21:17. “In proper names,” says Fürst, “those of cognate senses were often interchanged.” In 2 Kings 8:26 he is said to be 22 years old when he began to reign; but in 2 Chronicles 22:2 it says he was 42. The latter is doubtless a mistake of some copyist, for his father was only 40 years old when he died (2 Chron. 21:5, 20). The Syriac and Arabic copies read 22 in both passages.

Strong’s Dictionary of Hebrew Words:

or (prolonged) rAchazyahuw {akh-az-yaw'-hoo}; from 270 and 3050; Jah has seized; Achazjah, the name of a Jewish and an Israelite king
KJV Usage:

Jackson’s Dictionary of Scripture Proper Names:

possessed of Jehovah

Potts’ Bible Proper Names:

The Lord took; the Lord sustains:―name of a Jewish and an Israelite king [AZARIAH and JEHOAHAZ], 1 Kings 22:40. {Apprehendit Dominus}