阿部定
is a Japanese actor, stage actor and musician from Matsudo, Chiba Prefecture. He started his acting career after joining a theater company/talent agency, Otona Keikaku, in around 1992 and gained his popularity after the drama series "Team Medical Dragon" and as being the lead singer of the Japanese comedy rock band Group Tamashii. His stage name is a pun on notorious geisha Sada Abe.