Boyd’s Bible Dictionary:

(uncle). (1) Seventh king of Israel. Reigned B. C. 919-896 (1 Kings 16:29). Married Jezebel of Tyre, who introduced the worship of Baal and Astarte. One of the most notorious of O. T. characters. Slain by a chance arrow, and the “dogs licked his blood” according to prophecy (1 Kings 18-22; 2 Chron. 18). (2) A false prophet at Babylon (Jer. 29:22).

Concise Bible Dictionary:

1. Son and successor of Omri, king of Israel. He married Jezebel, daughter of Ethbaal, king of the Zidonians, and under her influence became an idolater, and led Israel into the worship of Baal. Of him it is said, there was none like him in very abominably following idols. It was chiefly in his reign that Elijah the Tishbite labored, and he testified for Jehovah against the apostasy and corruption of the king. The trial of fire from heaven is an especial instance of this, which was followed by the death of 450 of the prophets of Baal (1 Kings 18:19-40), but there was no repentance in the king. Ahab made two attacks on Benhadad king of Syria and was helped by God so that he obtained the victory; on the second occasion instead of destroying Benhadad (whom the Lord had doomed to destruction) he made a treaty with him.
Ahab coveted the vineyard of Naboth, but on his refusal to part with the inheritance given by God to his fathers, Jezebel caused his death and bade Ahab take possession of the vineyard. Elijah met him there and declared that dogs should lick his blood where they had licked the blood of Naboth. The dogs should also eat Jezebel, and Ahab’s house should be cut off. Ahab humbled himself before God, and the full end of his house was delayed till his son’s days. After this Ahab made another attack upon Syria, and his 400 prophets foretold that he would be successful; and he, though warned of his danger by the prophet Micaiah, went into battle accompanied by Jehoshaphat king of Judah, his ally. He disguised himself, but an arrow, shot at a venture, smote him between the joints of his armor, and he was wounded to death, and the prediction of Elijah came literally to pass (1 Kings 21:22). Grace had lingered over this poor idolater, for he was an Israelite; but he died impenitent, and his whole house was soon to perish (2 Kings 9:7-10). The judgment of God fell on the apostate king who had seized the inheritance of God’s people.
2. A false prophet among the captives of Babylon who prophesied a lie, and was roasted in the fire by Nebuchadnezzar (Jer. 29:21-22).

Strong’s Dictionary of Hebrew Words:

once (by contraction) oEchab (Jer. 29:22) {ekh- awb'}; from {SI 10251}251{/SI} and 1; brother (i.e. friend) of (his) father; Achab, the name of a king of Israel and of a prophet at Babylon
KJV Usage:

Jackson’s Dictionary of Scripture Proper Names:

brother of father

Potts’ Bible Proper Names:

Brother, or friend, of his father; uncle:―the name of a king of Israel, 1 Kings 16:28. {Frater, sive amicus, patris}