isthmus
Drake Passage separates South America and Antarctica. It is a narrow stretch of water connecting the southern Atlantic and southern Pacific Oceans.
The Isthmus of Panama separates North America from South America. It is also known as the Isthmus of Darien, and is a narrow strip of land that is in between the Caribbean Sea and Pacific ocean.
Strait
The body of water that separates France and the United Kingdom is called the English Channel. It is a narrow stretch of water that connects the Atlantic Ocean to the North Sea.
The narrow body of water that separates Tierra del Fuego from South America is The Strait of Magellan. The strait also separates other islands from South America.
The narrow strip that separates Spain from Africa is the Strait of Gibraltar.
the bering strait
It is a channel
The Bering Strait separates North America from Asia. It is a narrow passage of water between the eastern tip of Russia and the western coast of Alaska.
isthmus of panama
A River or a Stream. I would say Tidal Bore