Noun third battle of ypres has 1 sense
  1. Ypres, battle of Ypres, third battle of Ypres - battle in World War I (1917); an Allied offensive which eventually failed because tanks bogged down in the waterlogged soil of Flanders; Germans introduced mustard gas which interfered with the Allied artillery
    --1 is a kind of pitched battle
    --1 is a part of
     World War I, World War 1, Great War, First World War, War to End War
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