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(compulsory) retirement age; age limit
(compulsory) retirement (on reaching retirement age); mandatory retirement
minimum years of service at a particular rank before eligibility for promotion (in the Imperial Japanese Army and Navy)
定年退職後は長年の趣味の釣りに時間を使いたい。
After retirement, I want to spend time on fishing, my long-time hobby.
私の父は来年定年を迎える予定だ。
My father is scheduled to reach retirement age next year.
少子高齢化対策として定年退職の年齢が引き上げられた。
The retirement age has been raised.