Lao Tone Mai Tho

It marks tone within a Lao syllable. Mai tho works with the initial consonant (the syllable’s first consonant) and the syllable type. Lao groups consonants into tone classes, and an open syllable ends in a vowel. In the rule set shown here, a high- or middle-class initial consonant gives a falling tone; a low-class one gives a high tone. Read the whole spelling to know the pronunciation.

The history of the Lao tone mark follows the development of the script. Lao writing developed through the Sukhothai and Fak Kham script traditions. Fak Kham is described as a prototype—an earlier model—of Lao script, which later developed local forms. The Tha Khaek stele, an inscribed stone monument, is dated 17 April 1494 and described as the earliest apparently genuine example of Lao script. Earlier rock writing near Luang Prabang has also been reported, but it is not secure enough to settle when Lao script began. That date does not prove when this particular mark first appeared.

Mai tho’s spoken result varies across Lao varieties, although its spelling role stays similar. The Thai mark ้ belongs to a related script tradition, but it is a separate Thai character.