The Collaborative International Dictionary of English v.0.48:

Baal \Ba"al\ (b[=a]"al), n.; Heb. pl. Baalim (-[i^]m). [Heb.
   ba'al lord.]
   1. (Myth.) The supreme male divinity of the Phoenician and
      Canaanitish nations.
      [1913 Webster]

   Note: The name of this god occurs in the Old Testament and
         elsewhere with qualifying epithets subjoined, answering
         to the different ideas of his character; as,
         Baal-berith (the Covenant Baal), Baal-zebub (Baal of
         the fly).
         [1913 Webster]

   2. pl. The whole class of divinities to whom the name Baal
      was applied. --Judges x. 6.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Bel \Bel\, n.
   The Babylonian name of the god known among the Hebrews as
   Baal. See Baal. --Baruch vi. 41.
   [1913 Webster]

WordNet (r) 3.0 (2006):

Baal
    n 1: any of numerous local fertility and nature deities
         worshipped by ancient Semitic peoples; the Hebrews
         considered Baal a false god

The Devil's Dictionary (1881-1906):

BAAL, n.  An old deity formerly much worshiped under various names.
As Baal he was popular with the Phoenicians; as Belus or Bel he had
the honor to be served by the priest Berosus, who wrote the famous
account of the Deluge; as Babel he had a tower partly erected to his
glory on the Plain of Shinar.  From Babel comes our English word
"babble."  Under whatever name worshiped, Baal is the Sun-god.  As
Beelzebub he is the god of flies, which are begotten of the sun's rays
on the stagnant water.  In Physicia Baal is still worshiped as Bolus,
and as Belly he is adored and served with abundant sacrifice by the
priests of Guttledom.