old age; advanced in years; 老龄
school-age children; 学龄儿童
length of military service; 军龄
length of service; years of service 工龄
adult instar; 成虫龄
larval instar; 幼虫龄
牛津高阶第八版
美国韦氏词典
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维基百科 (自由的百科全书)