The Probert Encyclopaedia of General Information

FLAG

In its most popular usage, a flag is a piece of bunting, usually but not always, square or rectangular in shape, attached to a pole and used as a standard, ensign or signal for display or decoration. Formerly in Britain, a black flag was raised outside prisons to announce the execution of a prisoner. Traditionally in Britain, when in mourning flags are lowered to halfway down the pole and 'flown at half mast'.
Research Flag