Dating vowel lengthening in Thai
This paper dates vowel lengthening in Thai, which affected words that originally had a long vowel such as cʰaːw4 ‘morning’, naːm4 ‘water’, maːj4 ‘wood’, and daːj3 ‘to acquire’. Analysis of data from rhymming patterns in poetry, and from dictionaries and grammar books for foreigners shows that the vowel lengthening began in the late 24th century