'Unclean' in the Bible

And in the synagogue was a man, having a spirit of an unclean demon, and he cried out with a great voice,

and amazement came upon all, and they were speaking together, with one another, saying, 'What is this word, that with authority and power he doth command the unclean spirits, and they come forth?'

and those harassed by unclean spirits, and they were healed,

For he commanded the unclean spirit to come forth from the man, for many times it had caught him, and he was being bound with chains and fetters -- guarded, and breaking asunder the bonds he was driven by the demons to the deserts.

and as he is yet coming near, the demon rent him, and tore him sore, and Jesus rebuked the unclean spirit, and healed the youth, and gave him back to his father.

'When the unclean spirit may go forth from the man it walketh through waterless places seeking rest, and not finding, it saith, I will turn back to my house whence I came forth;