from a turk word 'wolf' or from a russian word, 'eager to fight, famous and brave', - cfr also Borislav,
registered for the first time in the case of the Bulgarian ruler
Prince Boris I (852-889), who adopted Christianity in 864 and imposed it to his entire people, also a Tzar-name

fra et tyrkisk ord for ’ulv’ el. ’liten’ evt russ. ’strid-berømt’ – registrert første gang hos Boris 1. konge av Bulgaria som innførte kristendommen der i 864

Boris Pasternak russisk dikter d 1960