* Geography: "The Mississippi River has many tributaries, including the Missouri and Ohio Rivers."
* Figurative: "Her work was a tributary to the great artists who came before her." (meaning her work was influenced by or paid homage to them)
* Formal: "The smaller nations were forced to become tributaries to the powerful empire." (meaning they were forced to pay tribute or taxes)
Let me know if you'd like more examples or want to explore specific contexts for using the word!