Ohio is a state in the United States. Historically a part of the Midwest, Ohio is a cultural and geographical crossroads, which was settled by people from New England, the Middle States, Appalachia, and the upper south. "This slice of the mid-west contains a bit of everything American—part north-eastern and part southern, part urban and part rural, part hardscrabble poverty and part booming suburb," notes The Economist.A grain of sand for your thoughts", The Economist, December 20, 2005, retrieved December 23, 2005. Prior to 1984, the United States Census Bureau considered Ohio part of the North Central Region."Geographic Definitions"Census Region definition, United States Census Bureau, retrieved December 22, 2005. That region concept was renamed "Midwest" and split into two divisions. Ohio is now in the East North Central States division."Geographic Definitions" Census Region definition Attachment C, United States Census Bureau, retrieved December 22, 2005.

Ohio was the first state admitted to the Union under the Northwest Ordinance. Its U.S. postal abbreviation is OH; its old-style abbreviation is O. Ohio is an Iroquois word meaning "good river." The name refers to the Ohio River that forms its southern border.

The United States Navy has named several ships USS Ohio in honor of this state.