Overview
Bey is a Turkic title for a chieftain, and an honorific, traditionally applied to people with special lineages to the leaders or rulers of variously sized areas in the numerous Turkic kingdoms, emirates, sultanates and empires in Central Asia, South Asia, and the Middle East, such as the Ottomans, Timurids or the various khanates and emirates in Central Asia and the Eurasian Steppe. The feminine equivalent title was begum. The regions or provinces where "beys" ruled or which they administered were called beylik, roughly meaning "governorate" and/or "region" (the equivalent of county in other parts of Europe). However the exact scope of power handed to the beks (alternative spelling to beys) varied with each country, thus there was no clear-cut system, rigidly applied to all countries defining all the possible power and prestige that came along with the title.
Today, the word is still used formally as a social title for men, similar to the way the titles "sir" and "mister" are used in the English language. Additionally, it is widely used in the naming customs of Central Asia, namely in countries such as Uzbekistan, Tajikistan, Kazakhstan and Kyrgyzstan. Notably, the ethnic designation of Uzbeks comes from the name of Öz Beg Khan of the Golden Horde, being an example of the usage of this word in personal names and even names of whole ethnic groups. The general rule is that the honorific is used with first names and not with surnames or last names.
Etymology
The word entered English from Turkish bey, itself derived from Old Turkic beg, which – in the form bäg – has been mentioned as early as in the Orkhon inscriptions (8th century AD) and is usually translated as "tribal leader". The actual origin of the word is still disputed, though it is mostly agreed that it was a loan-word, in Old Turkic. This Turkic word is usually considered a borrowing from an Iranian language. However, German Turkologist Gerhard Doerfer assessed the derivation from Iranian as superficially attractive but quite uncertain, and pointed out the possibility that the word may be genuinely Turkic. Two principal etymologies have been proposed by scholars:
the Middle Persian title bag (also baγ or βaγ, Old Iranian baga; cf. Sanskrit भग / bhaga) meaning "lord" and "master". Peter Golden derives the word via Sogdian bġy from the same Iranian root. All Middle Iranian languages retain forms derived from baga- in the sense "god": Middle Persian bay (plur.
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