Definitions for "O Sensei"
Japanese, The honorific prefix "O" attached the word " Sensei" indicates respect and acknowledgment of the chief instructor of a system. Most commonly associated with Ueshiba Morihei, founder of modern day Aikido.
title of respect usually reserved for founder of an art
(oh-sen-say)(great teacher) - term referring to Morihei Ueshiba, founder of Aikido