Waterloo: [19] The decisive battle at which the army of Napoleon was finally defeated by British, Dutch, and Prussian forces was fought just outside the village of Waterloo, near Brussels in Belgium, on 18 June 1815. The word Waterloo soon came to be used metaphorically for a ‘final and crushing defeat, something that puts one hors de combat for ever’. The first record of this new application comes in a letter written in 1816 by Lord Byron to his friend Thomas Moore: ‘It [Armenian] is … a Waterloo of an Alphabet’.
