'Uncleanness' in the Bible

The {Israelites} who returned from the exile and all those who separated themselves from the uncleanness of the nations of the earth to seek Yahweh the God of Israel, ate.

which you commanded by the hand of your servants the prophets saying, 'The land that you are entering to possess is a land of impurity with the impurity of the peoples of the lands, with their detestable things which they have filled from end to end with their uncleanness.