Unveiling Denasalization as an Ongoing Sound Change: The Role of Prosody and Gender in Seoul Korean

This study examines variation in coarticulatory vowel nasalization in Seoul Korean as a function of prosodic boundaries and gender, exploring its role in an emerging denasalization sound change. Coarticulatory vowel nasality, measured by A1-P0, was analyzed in the word-initial vowels of /ma.mi/ across three prosodic boundary conditions (IP-initial, AP-initial, and Wd-initial) in 35 speakers in their 20s. Results show that phrase-initial vowels exhibit reduced nasality as part of domain-initial articulatory strengthening, suggesting that denasalization of word-initial nasal consonants extends to the following vowel, reducing its coarticulatory nasalization and thus signaling the progression of a position-driven sound change. Significant gender differences were found: male speakers consistently adhere to this change throughout the vowel, exhibiting greater reductions in coarticulatory vowel nasalization in phrase-initial contexts. In contrast, female speakers retain higher nasality levels in both phrase-initial and phrase-medial positions by regulating the coarticulatory process. These gender-related differences may reflect socially grounded perceptions of nasality and/or female speakers' tendency to preserve phonological features, influencing speech production choices. These findings highlight the interplay between prosodically driven phonetic variation and gender: speakers actively control the degree of vowel nasalization, and this phonetic variation, in turn, is further shaped by gender, potentially evolving into a systematic sound change.