(n.) The quality or state of being senior.

aboriginality accomplishment age ancien regime ancientness antiquity ascendancy atavism authority cobwebs of antiquity consequence deanship dust of ages eld elderliness eldership eminence excellence favor great age greatness hoary age hoary eld importance incomparability influence influentialness inimitability inveteracy lead majority moment old age old order old style oldness one-upmanship precedence predominance predomination preeminence preponderance prepotence prepotency prerogative pressure prestige primitiveness primogeniture primordialism primordiality priority privilege prominence rank right-of-way senility skill stature success superiority transcendence transcendency venerableness virtuosity weight weightiness