Edited sentence: Columbia (name) is a name for the Americas, including both North and South America.Columbia, the country, however, has taken this name for the Americas as the name of its country.Exactly the same problem happens with use of the words Columbia and Columbian.People in the United States have used Columbia as a name for the United States, even prior to Columbia being named.Similar to the way Americans is used in the United States, people from Columbia are called Columbians.The capital of the United States sits on the District of Columbia