The years of James Joyce’s life (1882-1941) coincide with a period of transition in the history of Western linguistics, during which the focus on history, which had characterized the writings on language of generations of thinkers for centuries, was slowly but surely superseded by the structuralist approach. Crucial in that transitional process was the emergence of semantics at the close of the nineteenth century, an allegedly scientific discipline in whose birth the architects of the Oxford English Dictionary were instrumental, and which Michel Bréal, in France, later placed on a firm institutional footing. While scholars, until then, had been engrossed in a quest for so-called “universals” and for the origins of human speech, coming up with all sorts of theories to account for resemblances between given tongues, their time and energy were now devoted to sifting out textual evidence in order to trace out the subtle shifts in meaning of particular words. This new direction in language study went hand in hand with the increasing sophistication of comparative philology, which, thanks to the elaboration of evermore precise phonetic laws, contributed to the emergence of linguistics as a science in its own right.James Joyce, who is known to have pored over Richard Trench’s On The Study of Words (1851) and Walter Skeat’s Etymological Dictionary (1882) in his early years as a writer, was heavily influenced by this major development. The aim of my paper will be to analyse the way that impact is registered in A Portrait of the Artist as a Young Man, which was written and published in the very years during which Ferdinand de Saussure, in the seminars he was giving in Geneva, was striving to give scientific credentials to the study of language, and thereby revolutionizing it. I will focus on precise passages of A Portrait, such as those in which Stephen muses over the words “god,” “suck,” and “ivory,” to show that his realisation of the illusoriness of the supposedly direct link between words and single objects, and the filling up of that gap with meaning, is not merely a necessary and elementary first stage on his way to artistic maturity, but replays in miniature a key moment in the history of Western linguistic science, one which corresponds to the dramatic shift from the diachronic model to the synchronic one.