A river that flows for 980 miles (1,580 km) from Pittsburgh in Pennsylvania, where it is formed by the Allegheny and Monongahela rivers, through the eastern Midwest to join the Mississippi River at Cairo in Illinois.
Definition of Ohio River in US English:
Ohio River
proper noun
A river that flows for 980 miles (1,580 km) from Pittsburgh in Pennsylvania, where it is formed by the Allegheny and Monongahela rivers, through the eastern Midwest to join the Mississippi River at Cairo in Illinois.