adj. Furnishing aid; assisting; auxiliary; helping; tributary; especially, aiding in an inferior position or capacity; as, a subsidiary stream. Subordinate. Chief ruler and principal head everywhere, not suffragant and subsidiary. Of or pertaining to a subsidy; constituting a subsidy; being a part of, or of the nature of, a subsidy; as, subsidiary payments to an ally. Under another's control.
- n. pl. Subsidiaries. One who, or that which, contributes aid or additional supplies; an assistant; an auxiliary. - A company owned by a parent company. A company where the majority of its stock is owned by another corporation.