Lee, Dae-yong, Jiyeon Song, Sahyang Kim, and Taehong Cho. 2024. Some acoustic and articulatory characteristics of the three diphthongal vowels with /w/ in speech of young Seoul Korean speakers. Linguistic Research 41(1): 1-26. This study examines acoustic -articulatory properties of three Korean diphthongal vowels of /we/* '외', /we/ '왜', and /we/ '웨' in monosyllabic contexts with and without the onset /h/, produced by young Seoul female and male speakers in their twenties. (/we/* refers to the diphthongized vowel of the previous monophthong /o/.) Results indicate that the three diphthongs do not significantly differ in various phonetic measures, suggesting that they are largely merged. However, there is some evidence that young speakers still maintain a subtle phonetic difference between the 'new' diphthong (/we/*) and one of the 'old' diphthongs (/we, we/). The distinctions are further constrained by the onset context, complicating the results. For example, a difference between /we/* and /we/ is observed in articulatory Movement duration only with /h/. Additionally, there is an asymmetry between acoustic and articulatory measures such that a more pronounced distinction between /we/* and one of the 'old' diphthongs is observed in the articulatory dimensions, such as Movement duration, Displacement, and Tongue position. Finally, there is no evidence of a gender -related difference that suggests female speakers are leading the merger, while some distinctions between the 'new' and the 'old' diphthongs are made only by the female speakers, possibly due to their propensity to make distinctions reflected in the orthographic representations. These results are further discussed in their implications for the importance of multi -dimensional phonetic studies and the role of gender in understanding the nuanced extent of merger of the diphthongs. (Hanyang University center dot Hongik University)