Easton's Bible Dictionary

Baal-peor - lord of the opening, a god of the Moabites (Num. 25:3; 31:16; Josh. 22:17), worshipped by obscene rites. So called from Mount Peor, where this worship was celebrated, the Baal of Peor. The Israelites fell into the worship of this idol (Num. 25:3, 5, 18; Deut. 4:3; Ps. 106:28; Hos. 9:10).