a US state in the Middle West, also called the Show-Me State and, in former times, the Mother of the West. The largest city is Kansas City and the capital city is Jefferson City. Missouri was part of the Louisiana Purchase and became a state in 1821 under the Missouri Compromise. Its products include grain, beer, lead and aerospace equipment. Among places visited by tourists are the Gateway Arch at St Louis and the homes of President Harry S Truman at Independence and Mark Twain at Hannibal.