( ˌexpectation of ˈlife) the number of years that a person is likely to live 预期寿命◆Pension fund managers have to cope with longer life expectancy and new pension regulations. 退休金基金经理人需要面对更长的预期寿命和新的退休金条例。
the length of time that sth is likely to exist or continue for 预计存在（或持续）的期限◆the short life expectancy of dotcoms 昙花一现的网络公司
the length of time that an asset is likely to be used for 资产的预期使用期限