Oirats (Ойрад, Oirad, ɔiˈrɑt) or Oirds (Ойрд, Oird; Өөрд; 瓦剌), also formerly Eluts and Eleuths (厄魯特, Èlǔtè), are the westernmost group of the Mongols whose ancestral home is in the Altai region of Siberia, Xinjiang and western Mongolia.
Historically, the Oirats were composed of four major tribes: Dzungar (Choros or Olots), Torghut, Dörbet and Khoshut. The minor tribes include: Khoid, Bayads, Myangad, Zakhchin, Baatud.
The modern Kalmyks of Kalmykia on the Caspian Sea in southeastern Europe are Oirats.
The name derives from Mongolic oi < *hoi ("forest, woods") and ard < *harad ("people"), and they were counted among the "forest people" in the 13th century. Similar to that is the Turkic ağaç eri ("woodman") that is found as a tribal name such as Akatziri, an ancient tribe among European Huns, and as a place name in many locales, including the corrupted name of the town of Aghajari in Iran. A second opinion believes the name derives from Mongolian word oirt (or oirkhon) meaning "close (as in distance)," as in "close/nearer ones."
The name Oirat may derive from a corruption of the group's original name Dörben Öörd, meaning "The Allied Four". Perhaps inspired by the designation Dörben Öörd, other Mongols at times used the term "Döchin Mongols" for themselves ("Döchin" meaning forty), but there was rarely as great a degree of unity among larger numbers of tribes as among the Oirats.
These views are challenged by Kempf 2010, who from a historical linguist's point of view argues that the name is a plural coming from *oyiran, and eventually from Turkic *ōy 'a word for a colour of a horse's coat' (oy + gir suffix for colours + (A)n collective suffix).
Zaya Pandita and Clear Script
In the 17th century, Zaya Pandita, a Gelug monk of the Khoshut tribe, devised a new writing system called Clear Script for use by Oirats. This system was developed on the basis of the older Mongolian script, but had a more developed system of diacritics to preclude misreading and reflected some lexical and grammatical differences of the Oirat language from Mongolian.