Hayastan comes from the word Haik the legendary father of all armenians In the legend he kills Bell the King of Babylon. Armenians call themselves after Haik and with the rules of lingustics Haik can loose the "k" and be Hai (Hai means "Armenian" in Armenian) The word Armenian is said to come from two sources one of which states that the Armen tirbe of the Armenian highlands gave birth to the word Armenia, and another theory states that it was taken after the semi-legondary king Aram. (which was Aramu in the Urartian dynasty the first armenian kingdom)