Bombardier

noun

1. A bomber crew member who sights and releases bombs.
2. A non-commissioned officer rank in artillery, equivalent to corporal. Abbreviated Bdr.

   "Wikipedia: Bombardier (Bdr) and Lance Bombardier (LBdr or L/Bdr) are British Army ranks used in the Royal Artillery and Royal Horse Artillery instead of (respectively) Corporal and Lance Corporal. In the Canadian Forces, the Artillery Branch uses the ranks of Master Bombardier and Bombardier instead of Master Corporal and Corporal."

3. An artilleryman; a gunner.
4. A bombardier beetle.