Origin is uncertain and no consensus exists on its etymology to this day. Some of the theories are:
The word is of the same origin as ე-გრ-ისი(e-gr-isi, “Egrisi”) and მ-ე-გრ-ელ-ი(m-e-gr-el-i, “Mingrelian”). The fact that Guria was a historical region of Kingdom of Egrisi may be a proof of this. Marr, Javakhishvili and Ingorokva accept this etymology and reconstruct earlier *ეგურია(*eguria) (which developed from ეგრისი(egrisi) and into გურია(guria)).
According to another theory, the stem can be traced back to the name of a tribe, *გვერ-(*gver-), which developed from earlier *ჰიბერ(*hiber), *ჰბერ(*hber) (whence იბერია(iberia)) and *ჰივერ(*hiver), *ჰვერ(*hver) (whence ივერია(iveria)). However, there is no historical account of such tribe in the ancient world.
According to a less popular theory, the toponym developed from Mingrelianგურ-ი(gur-i, “heart”). Scholars claim, that Gurians were renown for their boldness and bitterness since the ancient times. Since the names of these qualities include the stem *გურ-(*gur-, “heart”) in Mingrelian (implying that these traits ascend from the heart of a man), this could be another indicator in this respect.
Bedošvili, Guram (2002) Kartul ṭoṗonimta ganmarṭebit-eṭimologiuri leksiḳoni [Dictionary of Georgian Geographical Names][1] (in Georgian), Tbilisi: Bakur Sulakauri Publishing, →ISBN
