1. [late 17C–18C] a spendthrift, a wastrel.
2. [late 17C–mid-19C; 1940s] (UK Und.; 1940s US) a pickpocket.
3. [early 19C+] (orig. UK; US black) usu. in pl., the fingers, esp. the middle and forefingers.
4. [mid-19C+] usu. in pl., the hands.
5. [late 19C+] the crotch; thus ext. as the penis.
6. [1980s] (Aus.) a jockey.
[1970s+] (Aus.) to work as a prostitute; the ‘fork’ is the juncture of the legs and thus the vagina.
see put one’s bones up under bone n.1