Mongolian Tsa ᠼ

Tsa writes a dental affricate, the sound English spells ts, and it is the twenty-ninth letter of the alphabet and one of the ten added for foreign vocabulary. Unicode encodes it at U+183C. The sound is common in Chinese and in Tibetan and is not part of the native Mongolian consonant system, which has the palatal affricates but not the dental one. The letter is one of the clearest cases of an addition made for a specific body of loanwords, since almost every Mongolian word containing it can be traced to one of those two sources. Its shape is adapted from a letter already in the alphabet, following the script's usual practice.

Alphabet charts place it among the additions, after the inherited twenty-five, which is the arrangement that keeps the alphabet honest about what belongs to Mongolian and what has been supplied for other languages. For a reader the letter functions as a marker in the same way an initial trill or an initial voiceless bilabial stop does: it identifies the word as borrowed before anything else about it is known, and in a religious text it points first to Tibetan. Unlike the two native affricates it has no voiced partner in the alphabet, since the voiced sibilant that would pair with it was itself added separately and writes a fricative rather than an affricate.

Tibetan is the language through which most of Mongolian Buddhism arrived, and its effect on Mongolian vocabulary is deep. Doctrinal terms, monastic offices, ritual objects, names of deities and titles of texts all came by that route, some translated into Mongolian and many simply taken over. The transfer was not phonetically neutral. Tibetan spelling preserves clusters that Tibetan itself no longer pronounces, and a Mongolian scribe copying a Tibetan word had to decide whether to write the spelling or the sound, which are different words.

Different periods and different translators answered differently, so the same term appears in Mongolian texts in more than one written form, and the variation is systematic enough to be a tool for dating and placing a manuscript. Tibetan remained a language of learning in Mongolian monasteries as well as a source of loanwords, so many texts are bilingual in practice, with Tibetan terms embedded in Mongolian sentences and written in Mongolian letters. Several of the added letters, this one among them, exist to make that possible with some accuracy rather than by approximation. The layer is thick enough that a reader working through a Mongolian Buddhist text without Tibetan will meet whole phrases that are Tibetan in everything but the shapes on the page.