A hand grenade is any small bomb that can be thrown by hand. A variety of types of hand grenades exists, the most common being explosive grenades designed to detonate after impact or after a set amount of time. Grenadiers were originally soldiers who specialized in throwing grenades. The word "grenade" derives from the French word for a "small explosive shell". Its first usage in English dates from the 1590s. It is likely derived from Old French pomegranate (influenced by Spanish granada), so called because the many-seeded fruit suggested the powder-filled, fragmenting bomb, or from similarity of shape.