Also, in recent use (1917), = a unique book.
1789. H. Walpole, Lett., 20 July. As rarities, a collector would give ten times more for them: and uniquity will make them valued more than the charming poetry. Ibid. (1793), Lett., 17 Sept. I lament that the summer is over; not because of its uniquity, but because you two made it so delightful to me.
1862. B. Taylor, Home & Abr., Ser. II. 399. The originality, the uniquity, of the place.
1886. E. Randolph, Mostly Fools, II. i. 16. The idea is unique, and uniquity, if I may permit myself the expression, is what we must aim at.
1898. Atlantic Monthly, LXXXII. 495/1. The lateness of the birds appearance, together with what a certain scholarly friend of mine would have called his uniquity.