WordNet (r) 3.0 (2006):

Ahab
    n 1: according to the Old Testament he was a pagan king of
         Israel and husband of Jezebel (9th century BC)

Easton's 1897 Bible Dictionary:

Ahab
   father's brother. (1.) The son of Omri, whom he succeeded as the
   seventh king of Israel. His history is recorded in 1 Kings
   16-22. His wife was Jezebel (q.v.), who exercised a very evil
   influence over him. To the calf-worship introduced by Jeroboam
   he added the worship of Baal. He was severely admonished by
   Elijah (q.v.) for his wickedness. His anger was on this account
   kindled against the prophet, and he sought to kill him. He
   undertook three campaigns against Ben-hadad II., king of
   Damascus. In the first two, which were defensive, he gained a
   complete victory over Ben-hadad, who fell into his hands, and
   was afterwards released on the condition of his restoring all
   the cities of Israel he then held, and granting certain other
   concessions to Ahab. After three years of peace, for some cause
   Ahab renewed war (1 Kings 22:3) with Ben-hadad by assaulting the
   city of Ramoth-gilead, although the prophet Micaiah warned him
   that he would not succeed, and that the 400 false prophets who
   encouraged him were only leading him to his ruin. Micaiah was
   imprisoned for thus venturing to dissuade Ahab from his purpose.
   Ahab went into the battle disguised, that he might if possible
   escape the notice of his enemies; but an arrow from a bow "drawn
   at a venture" pierced him, and though stayed up in his chariot
   for a time he died towards evening, and Elijah's prophecy (1
   Kings 21:19) was fulfilled. He reigned twenty-three years.
   Because of his idolatry, lust, and covetousness, Ahab is
   referred to as pre-eminently the type of a wicked king (2 Kings
   8:18; 2 Chr. 22:3; Micah 6:16).

     (2.) A false prophet referred to by Jeremiah (Jer. 29:21), of
   whom nothing further is known.


Hitchcock's Bible Names Dictionary (late 1800's):

Ahab, uncle, or father's brother