BAB, an Arabic word meaning "gate," used largely in place names in the Near East, as Bab-el-Mandeb (q.v.). The word was brought into greater prominence in the phrase "The Bab" as a designation for Mirza Ali Muhammad ibn Radhik, founder of Babiism (q.v.), on account of his taking the name Bab-ud-Din (Gate of the Faith) before spreading his teachings.