Chametz, also Chometz transliterated from Hebrew: חָמֵץ / חמץ, are leavened foods that are forbidden on the Jewish holiday of Passover. According to Jewish law, Jews may not own, eat or benefit from chametz during Passover. This law appears several times in the Torah; the punishment for eating chametz on Passover is the divine punishment of kareth ("spiritual excision"), one of the severest levels of punishment in Judaism.
Chametz is a product that is both made from one of five types of grain, and has been combined with water and left to stand raw for longer than eighteen minutes.
Read more about Chametz: Etymology, Torah Related Sources, Stringency, Removal of Chametz, Chametz Found During or After Pesach, Additional Ashkenazi Restrictions