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fixed number (of people); prescribed number (of regular personnel, students, etc.); quota; numerical limit; complement
capacity (of a bus, boat, theatre, etc.); seating capacity
このバスの定員は五十人だ。
The capacity of this bus is fifty people.
このバスの定員は五十名となっています。
This bus has a capacity of 50 people.
定員を超えたため入場を断られた。
We were turned away because the venue was over capacity.