Population aging refers to the course of social development in which the proportion of the elderly population continuously rises in the general population and as well as the aging of population age structure.

• 所谓人口老龄化，是指在一个国家或地区因人均预期寿命的不断延长而使老年人口在总人口中的比重上升和人口年龄构成老化的社会发展过程。