'Unleavened Bread' in the Bible

Take Aaron, and his sons with him, and the robes and the holy oil and the ox of the sin-offering and the two male sheep and the basket of unleavened bread;

And out of the basket of unleavened bread which was before the Lord he took one unleavened cake, and one cake of bread with oil on it, and one thin cake, and put them on the fat and on the right leg:

And on the fifteenth day of the same month is the feast of unleavened bread; for seven days let your food be unleavened bread.