Grenade
1. A pomegranate. (Now obsolete)
2. A small bomb or explosive missile that is detonated by a fuse and thrown by hand or shot from a rifle or launcher.
3. A glass container filled with a chemical such as tear gas that is dispersed when the container is thrown and broken.

The word is derived from the French grenade, and Spanish & Portuguese granada, a pomegranate, which the original grenades were supposed to resemble.
Hence grenadine, a syrup made from pomegranate, the island of Grenada, and the Grenadier Guards.
The OED records the first English use (with meaning 1) in 1532.