1. A narrow stretch of land that joins North America to South America and separates the Atlantic Ocean from the Pacific Ocean : The Isthmus of Panama.
2. The tropical islands, called the West Indies, are located in this sea : Caribbean Sea.
3. Aphysical division of North America around the Hudson Bay which has the oldest known hard rocks of the world : The Canadian Shield.
4. A river that flows northwards and drains into the Hudson Bay : River Meckenzie and River Nelson.