'Unclean Spirit' in the Bible

And I saw come out of the mouth of the dragon, and out of the mouth of the beast, and out of the mouth of the false prophet, three unclean spirits like frogs;

And he cried with a strong voice, saying: Fallen, fallen is Babylon the great, and is become a habitation of demons, and a hold of every unclean spirit, and a cage of every unclean and hateful bird;