Have your first whitewater rafting trip planned for the near future? If so, it will help to know some of the language that is used when navigating your raft down the river to help avoid any potential confusion. Eddy See something downstream that is sticking out of the water? This is known as an eddy rather than just an obstacle. An eddy is not just an obstacle that you can run into but typically creates calm water on the opposite side of it.