Forbidden to eat on Passover. Results when one of the five grains (barley, rye, oats, wheat, and spelt) or a derivative of it is allowed to remain, undisturbed, with water for more than 18 minutes. Chometz is also used to describe any product or utensil that is not Kosher for Passover.
refers to food products containing any grain (wheat, barley, rye, oats, or spelt) or grain derivative, not specially prepared for Passover use.