The Ordos vowel-phoneme system in word-initial syllables is similar to that of Chakhar Mongolian, the most notable difference being that it has [e] and [e:] instead of [ə] and [ə:].[4] In southern varieties, *ɔ merged into /ʊ/, e.g. while you still say ɔrtɔs in Ejin Horo Banner, it has become ʊrtʊs in Uxin or the Otog Front Banner.[citation needed] In contrast to the other dialects of Mongolian proper, it retains this distinction in all following syllables including in open word-final syllables, thus resembling the syllable and phoneme structure of Middle Mongolian more than any other Mongolian variety. E.g. MM /ɑmɑ/ Ordos /ɑmɑ/ Khalkha /ɑm/ 'mouth', Ordos /ɑxʊr/ Khalkha /ɑxr/ ([ɑxɑ̯r]) 'short; short sheep's wool'.[5] Accordingly, it could never acquire palatalized consonant phonemes. Due to their persistent existence as short non-initial phonemes, /u/ and /ʊ/ have regressively assimilated *ø and *o, e.g. *otu > /ʊtʊ/ 'star', *ɡomutal > /ɡʊmʊdal/ 'offence', *tʰøry > /tʰuru/ 'power'. An analogous change took place for some sequences of *a and *u, e.g. *arasu > /arʊsʊ/.[6]
Ordos retains a variant of the old comitative case and shares the innovated directive case.[7] The verb system is not well researched, but employs a notable innovated suffix, ⟨guːn⟩, that does not seem to adhere to the common division into three Mongolic verb suffix classes.[8]
The lexicon of Ordos is that of a normal Mongolian dialect, with some Tibetan and Chinese loanwords.[9]