Ohio ohio • ohioan · · · Info · Definitions · Characters · · Ohio · · Text Latin · · Script 4 · · Length 2 · · Syllables Definitions · · · (noun) a midwestern state in north central United States in the Great Lakes region. Synonyms: Buckeye State, OH. · · Noun Definition 1 (noun) a river that is formed in western Pennsylvania and flows westward to become a tributary of the Mississippi River. Synonyms: Ohio River. · · Noun Definition 2 Characters · · O latin capital letter o U+004F h latin small letter h U+0068 i latin small letter i U+0069 o latin small letter o U+006F