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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)
停年の引き上げを求める議論が活発になっている。
Discussions calling for an increase in the retirement age are becoming more active.
停年を迎えた社員に感謝状が贈られた。
A certificate of appreciation was presented to the employee who reached retirement age.
停年後も嘱託として働き続ける道を選んだ。
I chose to continue working as a contract employee after retirement age.