lifetime/'laɪftaɪm/

n. the period of time during which sb is alive

n. [C,常S] 一生，终生：He had seen two world wars in his lifetime. 他一生中见证了两次世界大战。

◇This is the chance of a lifetime. 这是一生一遇的机会。

◇a lifetime of experience 毕生的经验

构词life + time