The crossword solutions for the term OHIO OR MISSOURI are 'Ohio' and 'Missouri', both of which are rivers. The Ohio River is a 981-mile long river that flows through six states in the United States, including Ohio, West Virginia, Kentucky, Indiana, Pennsylvania, and Illinois. It is the largest tributary by volume of the Mississippi River. The Missouri River is the longest river in North America, stretching 2, 341 miles from its source in the Rocky Mountains of Montana to its confluence with the Mississippi River near St. Louis, Missouri. It is the primary water source for much of the central United States.