life cycle
noun [ C usually singular ] uk/ˈlaɪf ˌsaɪ.kəl/ us/ˈlaɪf ˌsaɪ.kəl/
生命周期;生活周期，生活史
the series of changes that a living thing goes through from the beginning of its life until death
They studied the life cycle of the frog. 他们研究青蛙的生命周期。
（某物可以使用的）生命期
the length of time that something lasts or can be used
Many of these technological products have only a very short life cycle. 这些技术产品的生命期都很短。