Green’s Dictionary of Slang

(Aus.) a woman; the inference is of a ‘loose character’.

1882		Sydney Sl. Dict. (2 edn) 1: Bart - A girl, generally applied to those of loose character.
1885		Bulletin (Sydney) 7 Nov. ‘A Police Court Ballad, / The Leery Barty, / By Her Bloke’ 20/1: So young a ‘bart,’ such a bloomin’ art, / Before that ‘beak’ was never seen! / The gal she swore a bloomin’ hoath / That loiterin’ she had never been.
1892		‘Fanny Flukem’s Ball’ in Bird o’ Freedom (Sydney) in J. Murray Larrikins (1973) 39: Fat Mag came down from Crown Street, / with little flat foot Poll / And Sally Jerks, the ice-cream bart, / And Bluey Murphy’s doll.
1894		Truth (Sydney) 14 Jan. 3/3: Alf Lawton and Clara Spencer evoke much applause by their spirited sketch of ‘The Larrikin Lovers.’ This might equally as well have been entitled ‘The Bloke and His Bart’.
1897		W.T. Goodge ‘Great Aus. Slanguage’ in Baker Aus. Lang. (1945) 117: And his ladylove’s his donah, / Or his clinah or his tart, / Or his little bit o’ muslin, / As it used to be his bart.
1943		Baker Popular Dict. Aus. Sl. (2nd edn).