Noun
English Wikipedia has an article on:hetaireiaWikipedia
hetaireia (plural hetaireias or hetaireiai)
(historical) A unit of the Byzantine emperor's bodyguard.
Khazar and Farghânian (Φάργανοι) mercenaries constituted part of the imperial Byzantine Hetaireia bodyguard after its formation in 840, a position that could openly be purchased by a payment of seven pounds of gold. Source: Internet