Definitions by Oskar1
hole
noun - A whitewater feature of a river in which part of the current drops into a relatively deeper space in the river bed, moves back up toward the surface, and then recirculates upstream. Some holes are large enough that objects in them can be recirculated many times, making them very dangerous. River runners refer to these as "keepers." Smaller holes can be surfed in a kayak or even a raft, and are sometimes described as being "sticky."