Final devoicing and deletion of /-d/ in Castilian Spanish

In the Spanish of north-western Spain, word-final /-d/ shows a remarkable variety of phonetic outcomes. Its possible realizations include voiced approximants, voiceless fricatives and voiced and voiceless plosives, in addition to the deletion of the segment. Here we examine this complex pattern of allophony in a corpus of conversational speech, focusing on the effect of the following phonological context. The results show that most commonly /-d/ is either deleted or realized as a voiceless fricative. Voiceless fricatives are found in all phrasal contexts, but with significantly higher frequency before pause than before a vowel, which is consistent with the hypothesis of diachronic extension of the devoicing from the former context to the latter. The devoicing of /-d/ is neutralizing. Voiceless fricative realizations of /-d/ do not differ from those of phonemic /-θ/ either in amount of voicing or in duration. This implies that deletion and devoicing represent two alternative patterns of reduction starting from [ð], since phonemic /-θ/ is not subject to deletion. Whereas the deletion of /-d/ has lexical exceptions, its devoicing does not. Among the majority of /d/-final words, for which deletion is possible, the relative frequency with which they undergo deletion vs. devoicing appears to vary substantially depending on the specific lexical item. That is, both position in phrase and lexical identity probabilistically determine the realization of /-d/. In addition to contributing to our understanding of the synchronic and diachronic phonology of word-final obstruents in Spanish, we consider the extent to which these data, showing variable word-final devoicing, may help us understand the historical evolution of the crosslinguistically common phenomenon of systematic word-final devoicing.