SYMBOL, n.
Something that is supposed to typify or stand for something else. Many symbols are mere "survivals"--things which having no longer any utility continue to exist because we have inherited the tendency to make them; as funereal urns carved on memorial monuments. They were once real urns holding the ashes of the dead. We cannot stop making them, but we can give them a name that conceals our helplessness.
--Ambrose Bierce - The Devil's Dictionary