The First World War largely directed the course of the 20th century. Fought on three continents, the war saw 14 million killed and 34 million wounded. Its impact shaped the world we live in today, and the language of the trenches continues to live in the modern consciousness. One of the enduring myths of World War I is that the experience of the trenches was not talked about. Yet dozens of words entered or became familiar in the English language as...