Anti-hiatus tendencies in Spanish: Rate of occurrence and phonetic identification

Abstract

Spanish normative grammar considers any two-vowel combination of /e/, /a/, and /o/ as a hiatus, accepting that they can be pronounced as a diphthong in lower basilects and/or informal registers. This paper analyzes speeches of educated speakers, performing an acoustic analysis of 60 segmental and suprasegmental features in 493 vowel sequences. Linear mixed-effects models suggest that two-vowel sequences of /e/, /a/, and /o/ are pronounced as diphthongs in 77.27% of cases; suprasegmental features (especially duration) are the most reliable cues to distinguish a hiatus from a diphthong in Spanish. These results call for a re-examination of diphthong classification in Spanish.