| A | B |
|---|
| runoff | water that flows over the ground surface rather than soaking in |
| tributary | a smaller stream or river that feeds into a main river |
| watershed | the land area that supplies water to a river system |
| divide | a ridge of land that separates one watershed from another |
| erosion | the process by which fragments of soil and rock are broken off from the ground surface and carried away |
| deposition | the process by which soil and fragments of rock are deposited in a new location |
| sediment | partcles of rock and soil that are moved by water or wind, resulting in erosion and depostion |
| headwaters | the many small streams that come together at the source of the river |
| flood plain | a broad, flat valley through which a river flows |
meander,  | a looping curve formed in a river as it winds through its flood plain |
| oxbow lake | the crescent-shaped, cutoff body of water that remains after a river carves a new channel |
| mouth | the point where a river flows into another body of water |
| delta | the area of sediment deposits that build up near a river's mouth |
| levee | a long ridge formed by deposits of sediments alongside a river channel |
