n. & adj.
n. (pl. -ies) 1 a river or stream flowing into a larger river or lake. 2 hist. a person or State paying or subject to tribute.
adj. 1 (of a river etc.) that is a tributary. 2 hist. a paying tribute. b serving as tribute. tributarily adv. tributariness n.
[ ME f. L tributarius (as TRIBUTE) ]