青年団 - Seinen-dan
where
青年 - youth
団 /traditional form 團/ - league; association; union; group.
https://ja.wikipedia.org/wiki/%E9%9D%92%E5%B9%B4%E5%9B%A3
Short history of this organization.
Among the many semi-governmental institutions that Japanese bureaucrats supervised in the pre–World War...
