Green’s Dictionary of Slang

inexperienced, naïve.

1832		Egan Bk of Sports 189: The affrighted Johnny Raw constables, perceiving their mistake, were about to bolt.
1870		Aus. Town & Country Jrnl (Sydney) 26 Nov. 16/3: ‘The bullocks will be found,’ thought l — regarding my Johnny Raw friend with the amused pitying look of an old hand.