deadly weapon n: an object whose purpose is to cause death or that when used as an instrument of offense is capable of causing death or sometimes serious bodily harm compare dangerous weapon NOTE: An unloaded firearm has been generally held to be a deadly weapon. Although usually distinct, the terms deadly weapon and dangerous weapon are sometimes used interchangeably.
Source: Merriam-Webster's Dictionary of Law ©1996. Merriam-Webster, Incorporated. Published under license with Merriam-Webster, Incorporated.