(n.) Long duration; lastingness.

Bronze Age Dark Ages Depression Era Golden Age Ice Age Iron Age Jacksonian Age Middle Ages New Deal Era Platonic year Prohibition Era Silver Age Steel Age Stone Age abidingness aboriginality aeon ages ancien regime ancientness annus magnus antiquate antiquity atavism become extinct become obsolete blue moon caducity century cheat the undertaker cobwebs of antiquity constancy continuance cycle cycle of indiction date day days decline defeat of time defiance of time develop diuturnity dodder durability durableness duration dust of ages eld elderliness eldership endurance epoch era eternity fade fail florid fossilize fust generation get along get on glacial epoch great age great year grow grow old grow up hoary age hoary eld indiction inveteracy lastingness life lifetime long long standing long time long while long-lastingness long-livedness longevity lose currency maintenance maturate mellow molder month of Sundays obsolesce old age old order old style oldness outdate perdurability perennation period of existence perish permanence perpetuity persistence primitiveness primogeniture primordialism primordiality right smart spell ripe ripen rust senectitude senescence senility seniority shake shrivel sink stability standing steadfastness superannuate survival survivance time totter turn gray turn white venerableness wane waste away wither wizen wrinkle years years on end