A flat piece of unleavened bread, resembling a large cracker, used by Jews in place of yeast bread during Passover. According to the biblical account of Passover, God directed the ancestors of the Jews to eat unleavened bread, rather than delay their departure from Egypt by waiting for bread to rise.
unleavened bread eaten by Jews during the holiday of Passover (Pesah) in commemoration of their Exodus from Egypt. The rapid departure from Egypt did not allow for the fermentation of dough, and thus the use of leavening of any kind is proscribed throughout the week-long holiday.