adj. & n.
adj. 1 serving to assist or supplement; auxiliary. 2 (of a company) controlled by another. 3 (of troops): a paid for by subsidy. b hired by another nation.
n. (pl. -ies) 1 a subsidiary thing or person; an accessory. 2 a subsidiary company. subsidiarily adv. subsidiarity n.
[ L subsidiarius (as SUBSIDY) ]