tributary /ˈtɹɪbjʊtəɹi/adjective 3noun 3forms 1 adjective3 •Yielding supplies of any kind; serving to form or make up, a greater object of the same kind, as a part, branch, etc.; contributing.The Ohio has many tributary streams, and is itself tributary to the Mississippi. •Related to the paying of tribute. •Subordinate; inferior.to grace his tributary gods — 1634 noun3 •A natural water stream that flows into a larger river or other body of water. •A vein which drains into another vein.The great saphenous vein is a tributary of the femoral vein. •A nation, state, or other entity that pays tribute.An earnest Coniuration from the King, / As England was his faithfull Tributary — 1599 formstributaries