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Borrowed from Japanese 若頭 (wakagashira, literally “junior head”).
waka gashira (plural waka gashira)
- A yakuza member ranking beneath the oyabun and responsible for seeing that his orders are carried out correctly.
2017, Ren Warom, Virology[1], Titan Books, →ISBN:I'm Umi, Oniji's waka gashira, and his eldest daughter. I will be leading the assault on the Cartel.