n.  重大事件，里程碑 ≈ milepost/landmark

n. 〔路边显示下一城镇距离的〕里程标

• Photography was once an expensive, laborious ordeal reserved for life's greatest milestones. 生命中的重大事件

• It was a huge milestone in the development of smartphones, which are now owned by a majority of American adults and are increasingly common across the globe. 智能手机发展进程上的里程碑

• The treatment of diabetes reached a significant milestone in the 1970s. 20世纪70年代，糖尿病治疗到达了一个重要阶段。

BrE /əˌbriːviˈeɪʃn/