In recent years one element of the cultural history of the Great War has concerned the question of the mobilisation of scientists and science in the conflict.Of special interest have been the physical sciences and their direct military application, as in the case of chemistry and engineering, but also the medical sciences whose practical applications have been of equal importance.Less attention has been paid to the social sciences, whose expansion is one of the most significant developments in the intellectual life of the pre-war period. Within this line of research,the aim of which is to set out a “science of war” that is also a science of the war, this article focuses upon the case of the lexicographers,philologists and grammarians who turned their attention to the study of the use of language in the trenches.This example leads us to examine the general conditions in which a new form of knowledge is developed in a particularly turbulent period.