'Unfaithfully' in the Bible

"Instruct the Israelis what to do if a man's wife turns astray so that she unfaithfully acts against him,

When he has had her drink the water, if she was defiled and had acted unfaithfully toward her husband, then the contaminated water that brings a curse will enter her and infect her, causing her abdomen to swell and her thigh to waste away. Then she is to be a cursed woman among her people.