Indifference to every religion.

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1821.  The transition is easy to mere Nihilism, and a total disregard of moral obligation.—T. Dwight, ‘Travels,’ ii. 238. (N.E.D.)

2

a. 1817.  In Religion they [the inhabitants of Kings and Queen’s Counties] are Episcopalians, Presbyterians, Quakers, Baptists, Methodists, and Nihilists.Id., iii. 333.

3