The term "Poilu" truly became a popular expression during the Great War. Some years ago, the few surviving veterans were referred to as the "last Poilus", and many books about the conflict have used the term in their titles. And yet, the word is more problematic than one might imagine, especially if trying to use it in a Belgian context.
Despite widespread belief, the word "Poilu" (hairy) has nothing to do with difficulties shaving in the trenches and the supposedly hirsute appearance of the soldiers. No army likes its soldiers to look slovenly when in uniform, and in addition, gas masks fit poorly over neglected beards. It was therefore exceptional for the combatants during the First World War to be poorly shaven, except perhaps during engagements that prevented the men from being relieved for long periods (which was rare in the case of Belgium, except during the battle of the Yser or the final offensive). The term actually dates back much further than 1914, as it was already in use in France during the Napoleonic era. "Etre un poilu" or "avoir du poil" (being hairy) meant being fearless: once again, whiskers were the mark of virility. The expression became popular in certain French barracks in the 19th century, and was a huge success during the Great War. But this success wan't unanimous: initially, a French soldier wouldn't refer to himself as a "Poilu". It was civilians and journalists, all non-combatants, in fact, who began to use the expression in order to pay homage to their defenders. The soldiers themselves would either reject "Poilu" as an artificial term, or adopt it in order to garner the respect that it elicited behind the lines. But it long retained a somewhat bookish and unnatural feel to it, with French soldiers frequently using more neutral terms such as "the men" or "the guys".