Lexington is a city in, and the county seat of, Lafayette County, Missouri, United States. The population was 4,726 at the 2010 census. Lexington is in western Missouri, within the Kansas City metropolitan area, approximately 40 miles east of Kansas City. It is the home of the Battle of Lexington State Historic Site, and of the former Wentworth Military Academy and College, which operated from 1880 to 2017.