Definition of "Jo"

"Its name is Samantha Jo, after Josiah and me. You know they call girls Jo and Josie a sight lately; its name is agreeable to Josiah and me, very.

1888, Marietta Holley, Josiah Allen's Wife as a P.A. and P.I.: Samantha at the Centennial, page 577

Name, Jo. Nothing else that he knows on. Don't know that everybody has two names. Never heerd of sich a think. Don't know that Jo is short for a longer name. Thinks it long enough for him. He don't find no fault with it. Spell it? No. He can't spell it.

1852 March – 1853 September, Charles Dickens, “Chapter XI”, in Bleak House, London: Bradbury and Evans, […], published 1853