In NY penal code section 265.01 it states:
A person is guilty of criminal possession of a weapon in the fourth degree when:
(1) He or she possesses any firearm, electronic dart gun, electronic stun gun, gravity knife, switchblade knife, pilum ballistic knife, metal knuckle knife, cane sword, billy, blackjack, bludgeon, plastic knuckles, metal knuckles, chuka stick, sand bag, sandclub, wrist-brace type slingshot or slungshot, shirken or “Kung Fu star
I found the definition of gravity knife and switchblade. Further a couple things like brass knuckles are a bit self explanatory, however, where can I find an official definition of these items?