Mongolian Ang: The Nasal That Cannot Begin a Word

Ang writes the velar nasal, the sound English spells ng at the end of sing, and it is the ninth letter of the alphabet. Its defining property is a restriction rather than a shape: no Mongolian word begins with it. The sound occurs freely inside words and at their ends, and never at their start, which is a constraint Mongolian shares with English and with a great many other languages. That has a consequence for the alphabet. Every other letter here has three positional forms, initial, medial and final, because every other letter can stand in all three places. A letter that cannot begin a word has an initial form only in the sense that a chart may print one for completeness.

Unicode encodes ang at U+1829. In transliteration it is usually written ng, which invites a reader to think of it as two sounds, and it is not: it is one nasal made at the same place in the mouth as the velar stops, and the alphabet treats it as one letter accordingly. The letter is a useful reminder that an alphabet records the sound system of a particular language, including that language's rules about which sounds may stand where, and that those rules are as much a part of the writing system as the shapes are.