Competing constructions in Italian: a diachronic study of NN compounds and their NPN counterparts

Abstract This study explores the diachronic competition between two Italian morphological constructions: Noun-Noun (NN) compounds and their rival Noun-Preposition-Noun (NPN) syntagmatic counterparts. Drawing on a vast data sample from the Google Books corpus, we trace the historical development of both structures, focusing on the interplay between these constructions from the 20th century to the present. Our analysis centers on two key patterns: subordinate NN compounds, such as trattamento rifiuti (‘waste treatment’), which involve two bare common nouns with implicit relationships, and NPN phrasal nouns, like casa di cura (‘nursing home’), which are lexicalized multiword expressions linked by a preposition. Through statistical and clustering techniques, we reveal that while most NNs and NPNs coexist, only a small fraction of NNs dominate diachronically. Moreover, we identify specific ‘niches’ where NN compounds prevail over their NPN rivals. The clustering analysis further highlights distinct historical trajectories, with certain NN types exhibiting sharp increases in frequency during specific time periods. These findings suggest that the competition between NN and NPN is shaped not only by diachronic trends but also by genre, context, and linguistic preferences. Overall, this research contributes to understanding how word formation strategies evolve and compete over time in Italian.