Why is the National Mall called a mall?

The National Mall in Washington D.C. is not truly a shopping mall, but rather a large, open park. The term "mall" in this context does not refer to a commercial shopping area, but rather comes from the word "mall" meaning a shaded promenade or walk. In the case of the National Mall, it refers to the broad, tree-lined avenue that stretches from the Lincoln Memorial to the Capitol Building.