The Thai script was adapted from Old Khmer in the 13th century during the reign of King Ramkhamhaeng, as noted by Cambridge University Press. Many Thai royal and temple terms such as Racha and Prasat are borrowed directly from Khmer. Thai and Khmer belong to different language families, with Khmer classified as Austroasiatic and Thai as Tai-Kadai, showing that Thai writing and high-register vocabulary were imported from Khmer sources. “The Thai script was based on Old Khmer letters, with adjustm