What is the meaning of the word "yazoo"?

Definitions:

  1. A river or stream that runs parallel to a larger river for a significant distance before eventually joining it. copy to clipboard NOUN
    • The small stream became a yazoo tributary, running along the Mississippi River before joining it miles downstream. copy to clipboard
  2. A river that rises in west central Mississippi and flows southwast to empty into the Mississippi River above Vicksburg. copy to clipboard NOUN
    • The Yazoo River flows through Mississippi, carrying a significant amount of water to the Gulf of Mexico. copy to clipboard