The study of a selection of terms relating to the pharmaceutical medical field of the ancient Occitan language allows us to describe the formation of the Provençal lexical heritage, which, more than others, is marked by heterogeneity. The oral dissemination of ancient recipes, the literary tradition of the Occitan medical school, the Latin heritage and the Catalan, Arab and Hebrew contributions constitute the foundations of the ancient Occitan medical pharmaceutical lexicon. The present work singles out the semantic relationships existing between the different names of plants and also the linguistic phenomena that underlie the formation and dissemination of this particular terminology, with specific regard to the Iberian Romance area.…