La non canonicità del tipo it. braccio // braccia / bracci: Sovrabbondanza, difettività o iperdifferenziazione?

The paper addresses the status of double plural forms like bracci / braccia ‘arms’. Three hypotheses are presented and evaluated: 1) overabundance (the two plural forms are alternative realizations of the plural cell in the paradigm of a single lexeme); 2) defectiveness (Acquaviva’s 2008 hypothesis: forms in –a are pluralia tantum lexemes, distinct form the ones with a singular in –o and a plural in –i); overdifferentiation (the forms in –a and –i realize distinct cells in the paradigm of a single lexeme). The paper argues against overdifferentiation, because the semantic difference between the two plural forms, when it exists, does not match the opposition between independently attested values of the number feature. Data from usage in a corpus of contemporary Italian suggest that in some cases the two plural forms represent a case of overabundance in the plural cell of the paradigm of single lexeme, while in other cases it is possible to argue that the form in –a belongs to a distinct lexeme (not necessarily defective).