Noun

• S: (n) feeder, tributary, confluent, affluent (a branch that flows into the main stream)

Adjective

• S: (adj) tributary ((of a stream) flowing into a larger stream)
• S: (adj) tributary (paying tribute) "a tributary colony"
• similar to
• antonym
• S: (adj) conducive, contributing, contributive, contributory, tributary (tending to bring about; being partly responsible for) "working conditions are not conducive to productivity"; "the seaport was a contributing factor in the growth of the city"; "a contributory factor"