perpetualadj.永久的；永恒的；一再往复的perpetual debenture[法] 永久债券perpetual extension持恒拉伸perpetual resources永恒资源perpetual insurance终身保险perpetual inventoryn.永续盘存perpetual copyright永久版权perpetual franchise永久特许perpetual structure永久结构perpetual disability永久无行为能力perpetual succession永久继承