This article proposes a classification of reduplicative structures in Sicilian and provides a detailed analysis of one such structure, which forms adverbs through complete reduplication of nominal lexemes or word forms (NN adv). We show that this construction is part of the basic morphology of Sicilian. This subject is of interest for two reasons. First, Sicilian morphology is only rarely addressed in the linguistic literature, and Sicilian itself is always treated only from a dialectological or philological point of view. Moreover, this article proposes a morphological analysis of NN adv reduplication, which is a rare phenomenon in Romance languages, and has consequently never been the object of an in-depth study, particularly not from a lexicalist perspective. While the literature on reduplication cross-linguistically highlights semantic values associated with plurality, verbal aspect, intensity, repetition and expressiveness, this article shows that reduplication can express a locative meaning.