A statue of Christopher Columbus in Chicago.
Columbus Day definition by Webster's New World
Webster's New World College Dictionary Copyright © 2010 by Wiley Publishing, Inc., Cleveland, Ohio. Used by arrangement with John Wiley & Sons, Inc.
a legal holiday in the U.S. commemorating the discovery of America by Columbus (Oct. 12, 1492), observed in most states on the second Monday in October
Columbus Day definition by American Heritage Dictionary
October 12, observed in the United States in commemoration of the landing by Christopher Columbus in 1492 in America, which became known as “the New World” because Europeans did not know that it had existed. Columbus Day is now officially observed on the second Monday in October.