Thai vowel sign sara uue

It marks Thai’s long ue vowel. The sound is made without rounding your lips; ue is a spelling in Roman letters, not two separate vowels.

The Thai name is สระอือ. With no final consonant, the spelling uses ือ, as in มือ. Before a final consonant, อ is omitted while ื remains, as in มืด. Vowel length distinguishes Thai words, so shortening this sound can change the word.

Where did this mark come from?

It developed within the Thai writing tradition. Its role is to represent a vowel sound, rather than a standalone idea.

An early form of Thai writing, the Sukhothai script, developed from Old Khmer. It is attested in Inscription 1, a text carved in stone from the late thirteenth century. That dates the script tradition, not this exact modern shape.

Vowel spellings varied across the late thirteenth through early fifteenth centuries. Some scholars interpreted this as a loss of short–long distinctions; a comparative study argues the distinction survived despite spelling variation. Related Lao writing has its own spelling rules, not interchangeable with Thai.

Why does ื appear above the consonant?

Typing order and display position differ. Enter the consonant first, then ื; the Thai font positions the mark above it.

An isolated ื can look detached because it lacks a consonant to sit over. It is a combining mark, not a complete Thai syllable or an emoji.