Sedalia (sĭdā`lyə), city (1990 pop. 19,800), seat of Pettis co., W central Mo.; inc. 1864. An agricultural shipping and distribution center as well as a regional service and shopping center, Sedalia has a great variety of manufactures, among which are apparel, consumer goods, electronic equipment, and ordnance. Formerly an important rail center with railroad shops, Sedalia is the site of the Daum Museum of Contemporary Art and hosts the annual Missouri State Fair. Whiteman Air Force Base is to the west.