the remainder or
reserve of
money or supplies; a remaining chance; a last resource. This expression comes from warships of the seventeenth to nineteenth centuries, where
shot (
projectiles for
discharge from a cannon or firearm) used to be stored in strong, locked containers called
shot lockers. A
shot in the locker literally meant that there was one
shot of ammunition still
left in the
shot locker. This expression then came to be used ashore by sailors to mean one still had some
money in his pocket or, conversely, not a
shot in the locker meaning that he had no
money in his pocket. A
shot in the locker was later used more generally to
refer to a remnant or
reserve of anything.