Chametz etymologically means "hot" and "pressed", so the most accurate translation in English should be chametz = "baked bread". But "chametz", in reality, comes from a root which means "to be sour". So where YHWH says (Exodus 12:20) to eat nothing with chametz "in it" - it literally means the material from which the bread is made - the mixture, i.e., chametz! If you have the chametz - get rid of it, if you have the baked bread (which has chametz in it), get rid of that!