'Clean' in the Bible

Of every clean beast thou shalt take to thee seven and seven, the male and his female; and of the beasts that are not clean two, the male and his female:

Of clean beasts, and of beasts that are not clean, and of birds, and of everything that creepeth upon the ground,

And Noah builded an altar unto Jehovah, and took of every clean beast, and of every clean bird, and offered burnt-offerings on the altar.