Definition of "johnny"

Willie Cox said they found him in the barn, shot bang through the head, and the young English johnny who'd been on the station learning farming - disappeared.

1913, Katherine Mansfield, Millie

His hand shook. A little water spilled down the front of the hospital johnny Sean wore.

1991, Stephen King, Needful Things

The women's toilet (as distinguished from the ladies' room in a speakeasy, the johnny at school, the little girls' room at a party in an apartment, and the wash-my-hands on a train) was clean enough.

1935, John O'Hara, BUtterfield 8, Ch. ix, page 279

Kitty Hofman came in the johnny.

1935, John O'Hara, chapter IV, in Appointment in Samarra, page 98

[H]e declared, like a real Irishman, that 'if he were a living man when he died, he would not give a single johnny of whisky either at his wake or his funeral.'

1867, William Dool Killen, Memoir of John Edgar, page 108