|Historically: Balkans, Caucasus, Northern China (presumably)|
Today: Volga region
The Oghur, Onogur or Ogur languages (also known as Bulgar, Pre-Proto-Bulgar or Lir-Turkic and r-Turkic), are a branch of the Turkic language family. The only extant member of the group is the Chuvash language. The first to branch off from the Turkic family, the Oghur languages show significant divergence from other Turkic languages, which all share a later common ancestor. Languages from this family were spoken in some nomadic tribal confederations, such as those of the Onogurs or Ogurs, Bulgars and Khazars. Some scholars consider Hunnic a similar language and refer to this extended grouping as Hunno-Proto-Bulgarian.
The Oghur languages are a distinct group of the Turkic languages, standing in contrast to Common Turkic. Today they are represented only by Chuvash. Extinct Oghur languages include Bulgar and Khazar.
There is no consensus among linguists on the relation between Oghur and Common Turkic and several questions remain unsolved:
The Oghur languages are also known as "-r Turkic" because the final consonant in certain words is r, not z as in Common Turkic.Chuvash: - Turkish: öküz - Tatar: ? - English: ox. Hence the name Oghur corresponds Oghuz in Common Turkic. Other correspondences are Com. ? : Oghur l (tâ? : tâl, 'stone'); s > ?; *? > ?; k/q > ?; y > j, ?; d, ? > ? > z (10th cent.) > r (13th cent.)"; ?d > z > r (14th cent.); a > ? (after 9th cent.).
Distinguished specialist in the history of Central Asia the late Denis Sinor believed that the differences noted above suggest that the Oghur-speaking tribes could not have originated in territories inhabited by speakers of Mongolic languages, given that Mongolian dialects feature the -z suffix. Equally eminent historian Professor Golden, however, has noted that there are many loanwords in Mongolic from Oghur, such as Mong. ikere, Oghur. *ikir, Hung. iker, Comm. ikiz (twins). and holds the contradictory view that the Oghur inhabited the borderlands of Mongolia prior to the 5th century.
The Oghur tribes are often connected with the Hungarians whose exoethnonym is usually derived from Onogurs (> (H)ungars). The Hungarians are of mixed Ugrian / Turkic heritage, with strong Oghur-Bulgar and Khazar influences. Hungarian has many borrowings from Turkic and Oghur languages: Hung. tenger, Oghur. *tengir, Comm. tengiz (sea), Hung. gy?r?, Oghur. jürük, Comm. yüzük (ring), and terms of equestrian culture ló (horse), nyereg (saddle), fék (bridle), ostor (whip). A number of Hungarian loanwords were borrowed before the 9th century, shown by sz- (< O?. ?-) rather than Comm. gy- (< O?. ?-): example Hung. szél, Oghur. *?äl, Chuv. ?il, Comm. yel (wind), Hung. sz?cs (tailor), Hung. sz?l? (grapes).