Grenade

A grenade is a small explosive projectile. It can be thrown by hand, launched by a rifle attachment, or launched by a dedicated launcher. A modern hand grenade generally consists of an explosive charge ("filler"), a detonator mechanism, an internal striker to trigger the detonator, and an arming safety secured by a transport safety. The user removes the transport safety pins before throwing, and once the grenade leaves the hand the arming safety gets released, allowing the striker to trigger a primer that ignites a fuze, which burns down to the detonator and explodes the main charge.

Wikipedia →