Darkhad dialect

Darkhad (also "Darkhat") is a dialect in-between Central Mongolian and Oirat still variously seen as closer to Oirat or as a dialect of Khalkha Mongolian with some Oirat features. However, it seems to have substantially assimilated to the Khalkha dialect since it first was described by Sanžeev, and some classificational differences seem to be due to what historical (or even ideal) state got classified. A population of 20,000 was reported in 2000. Speakers live mainly in the west of Lake Khövsgöl in the sums Bayanzürkh, Ulaan-Uul and Rinchinlkhümbe in the Khövsgöl Province of Mongolia.

In contrast to Oirat, it has /o/ and /u/ and a diphthongized equivalent of *ai. However, monophthongized of *ai can be encountered and more so in older language material, so it can be assumed that *ai > ɛː > ɛe due to Khalkha influence. Somewhat similar developments can be observed for other vowels, but as at least /n/ and /l/ can get palatalized, it is problematic whether palatalized consonants or fronted vowels have to be considered as phonemes. It patterns with the Oirat dialects of the Mongolian state in that it retains *ŋn and sometimes has *b > /m/. It doesn't have the Khalkh /ʊ/ and /u/ in non-first syllables, as these merged with /ɔ/ and /o/.

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