A mechanism for raising or lowering ships in a river that has rapids or waterfalls is called dam and lock system. It is a special kind of dam system.
A lock is the mechanism for raising and lowering ships in a river that has rapids or waterfalls. Locks are used to make navigation an easier task.
That's called an accidental sign.
There are no waterfalls on the river Thames.
A step like series of waterfalls are called a cataract
A Botanist is a person who studies plants but also studies waterfalls.
The movement where you shrug your shoulders is called a shoulder shrug. It involves raising your shoulders up toward your ears and then lowering them back down.
Potamophobia - Is the fear of running water. There isn't one specifically for waterfalls.
precipitatiopn
Rapids
Dk
A simple water-raising device that uses a lever is called a "well sweep." It typically consists of a long pole or lever attached to a bucket at one end and a counterweight at the other end. By lowering the bucket into the well and then raising it using the lever, water can be easily drawn up to the surface.
The term for the action of raising one eyebrow is called "eyebrow raising" or "raising an eyebrow."