What ꒚ means
It is a sorting mark, not a syllable to read aloud.
Yi writing appears on pottery, stone and bronze; Unicode cites a bronze bell dated 1485 as its oldest surviving example.
The Liangshan standard for Nuosu, a Yi language, was devised in 1974 and adopted in 1980 to unify writing. Its dictionary index follows the sorting marks in Chinese dictionaries, but Yi characters themselves are not derived from Chinese.
Technical and bibliographic: it marks dictionary indexing, not ordinary Yi text.
Don't confuse it with
1Questions people ask
1Why does ꒚ show as a box?
A font-coverage issue. ꒚ is a text character; the active font needs Yi Radicals support to display it.
How to type ꒚
꒚\A49ACodes and encoding1 code points
A visible symbol can contain several code points. JS .length counts UTF-16 units; UTF-8 counts bytes.
