Waka Sensei

Mitsuteru Ueshiba (植芝充央 Ueshiba Mitsuteru, born 1981) is the son of the current Aikido Dōshu, Moriteru Ueshiba. In keeping with the Iemoto system, he is expected to succeed his father as Dōshu. He is the great-grandson of Morihei Ueshiba, the Aikido Founder. From April 2012 he has been the acting-dojocho of Hombu Dojo. Mitsuteru Ueshiba is referred to as Waka-sensei (若先生) and this term was applied to Moriteru Ueshiba when II Dōshu Kisshomaru Ueshiba was still alive. Literally from Japanese language “Waka” means “young”, however in this case the meaning is completely different. In Japanese culture the term of “Waka”, is refer to the “successor” (後継者), the person that will continue after his father (in this case Dōshu). "Wikipedia"