Classifying “Lao” Ethnic Languages Spoken in Central Thailand Using Tonal Criteria: A Case Study of “Chachoengsao Lao”

In the linguistic literature on the languages of ethnic Lao in Thailand, labels such as “Lao” or “Lao Wiang” are often used to identify local dialects as Lao varieties. This study examines patterns of tonal splits and mergers in the linguistic varieties spoken by the so-called “Lao” ethnic groups in Chachoengsao Province, Thailand, to re-identify and reclassify the so called “Lao” languages collected from 124 participants at 50 locations. This study used the tone box concept (Gedney 1972) as a basic tool to analyse tonal patterns. The results indicate that the “Lao” ethnic languages of Chachoengsao can be classified into three main groups, namely Lao, Phuan and Hua Phan Tai Nuea. While the Lao varieties show typical tonal patterns of Lao dialects (B≠DL, C1=DL123 and/or C234=DL4), the other two groups show none of the patterns. The findings show that the patterns of tonal development labels are better criteria than ethnic labels in the identification of Lao groups.