Dagon

little fish; diminutive from dag = a fish, the fish-god; the national god of the Philistines (Judg 16:23). This idol had the body of a fish with the head and hands of a man. It was an Assyrio-Babylonian deity, the worship of which was introduced among the Philistines through Chaldea. The most famous of the temples of Dagon were at Gaza (Judg 16:23-30) and Ashdod (1Sam 5:1-7). (See FISH)

EBD - Easton's Bible Dictionary