adjective /ˈmæn.dəˌtɔ.ɹi,mænˈdeɪtəri/
a) Obligatory; required or commanded by authority.
Attendance at a school is usually mandatory.
b) Of, or relating to a mandate.
This kind of immediate control structure we take to be characteristic of the tribe, and it leads to a rather rigid type of system in which every action not mandatory is forbidden.
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