noun; foot garment used by flatchested females or underendowed males to create an illusion of fullness or "bulge"
verb; to use sock(s) for above purposes
(noun) police and military slang for a "plant gun" -- gun placed near or on a suspect by the arresting official as fake evidence of threat.
The term "sock" is used because the plant gun is usually "found" in the suspect's sock, where it is easiest to conceal the act of planting the evidence. In military war zones, it is an illegal but common practice to keep a steady supply of plant guns handy