What does "collusion" mean?

Collusion: (Law) An agreement between two or more persons to defraud a person of his rights, by the forms of law, or to obtain an object forbidden by law. Bouvier. Abbott. A person who is guilty of connivance intentionally overlooks, and thus sanctions what he was bound to prevent. A person who is guilty of collusion unites with others (playing into their hands) for fraudulent purposes.