The traditional idea that the lexicon is an inventory of idiosyncratic and irregular entities has been questioned by several theoretical frameworks. Various approaches have shown the existence of regular schemas beyond the lexicon. This paper aims at analyzing the domain of Italian complex prepositions, through the description of synchronic and diachronic
features of such structures. Italian complex prepositions deserve special attention due to their high frequency of use and the related grammatical value. The quantitative analysis of Old and Contemporary Italian lexicon reveals that there is a major difference between complex prepositions in terms of type/token frequency. Furthermore, the analysis of syntactic formats among different diachronic phases i) sheds new light on the evolution of these structures and ii) puts into relation the fixedness, the syntagmatic structure and degree of grammaticalization of complex prepositions with their frequency of use
