Green’s Dictionary of Slang

(US) to prod with a knife, to stab.

1984		A. Sample (con. mid-1930s-early 1940s) Racehoss 95: took the boy scout knife pocketknife out of my overalls [...] When I bent over this time I gigged him in the thigh and fled.
1995		(con. 1985–90) P. Bourjois In Search of Respect 79: The more he tried to escape [...] the more I was jigging him. And I had a big 007. I wasn’t playing, either. I was serious. I would have jigged him.