an annuity shared by subscribers to a loan or common fund, the shares increasing as subscribers die until the last survivor enjoys the whole income 汤鼎氏养老金制,联合养老制(承购者共同使用一笔贷款或基金,生者的份额随死者的增加而增加,直至最后一个生者享受所剩的全部储金)
语源
mid 18th cent.: from French, named after Lorenzo Tonti (1630–95), a Neapolitan banker who started such a scheme to raise government loans in France (c.1653)