Green’s Dictionary of Slang

a woman.

1846		New Swell’s Night Guide to the Bowers of Venus 18: Here may you, ushered into a room, after admittance obtained from some well-known bona, through a window, see females in an actual state of nudity.
a.1890		broadside ballad in Farmer & Henley Sl. and Its Analogues I (1890–1904) 279/2: Girls are in vulgar called donas, / Some are called Miss and some Mrs., / The best of them all are called bonas.
1890–1904		Farmer & Henley Sl. and Its Analogues.