Named after the Ohio River. The river is the original meaning of the name Ohio, together with the Allegheny River, which the native peoples considered to be the same river (see also Allegheny River Boulevard). There is some disagreement about the etymology of this name. William Bright says that it comes from the Seneca name ohi:yó, derived from ohi:yo:h, “good river.” Annie Clark Miller says it is a fragment of the Lenape (Delaware) name “Ohiopeekhanne,” whose parts she translates as “Hanne, a stream; Peekhanne, the mainstream; Ohio, descriptive of the water whitened by the froth.” A 1936 article in the Post-Gazette gives the origin as an Iroquois word Ohionhiio, meaning “beautiful river.”
There is also a West Ohio Street on the other side of Allegheny Commons, from Ridge Avenue to Western Avenue. The two Ohio Streets were originally two halves of the same continuous street, on either side of the intersection with Federal Street.
Bright, William. Native American Placenames of the United States. University of Oklahoma Press, Norman, 2004. ISBN 978-0-8061-3576-2, 978-0-8061-3598-4.
Miller, Annie Clark. Early Land Marks and Names of Old Pittsburgh: An address delivered before the Pittsburgh Chapter Daughters of the American Revolution at Carnegie Institute, Nov. 30, 1923. Pittsburgh Chapter Daughters of the American Revolution, 1924, p. 6. Historic Pittsburgh 00awn8211m; Internet Archive earlylandmarksna00mill.
“Street names sketch history of city: Tribute to many pioneers dimmed by time.” Pittsburgh Post-Gazette, Sept. 26, 1936, anniversary section IV, p. 16. Newspapers.com 88921069.