Contributory

Part of speech: noun (n.)

One who contributes, or is liable to be called upon to contribute, as toward the discharge of a common indebtedness. Abbott.

Part of speech: adjective (a.)

Contributing to the same stock or purpose; promoting the same end; bringing assistance to some joint design, or increase to some common stock; contributive. Milton. Bonfires of contributory wood. Chapman. Contributory negligence (Law), negligence by an injured party, which combines with the negligence of the injurer in producing the injury, and which bars recovery when it is the proximate cause of the injury. Wharton.