Ararat - Is the name of historical Armenian Big Mount that later became a name. The origin of the biblical name isn't etymologically established. G. Ghapantsyan connects this name withUrartu ethnik term which later changed into arart (Ar+art "field") i. e. "Ara's field ". But it is a colloquial not scientific explanation.
Pogosyan - Poghossian, Pogossyan, Poghosyan, Poghosian, Pogosyan, etc., is an Armenian surname.
The Western Armenian equivalent is Boghossyan.