Non-plus

A fourth exclusive privilege of Universalists is, the possession of all the common sense, learning and piety in Christendom. Their effrontery abashes and non-pluses meeker men, who know not what to say to such dashing impudence.

Source: wiktionary

He was not of the Number of thoſe hot-headed, fiery Princes who are guided merely by the Impulſes and Motions of a temerarious Valour which is inſenſible to all Danger, and who precipitate themselves headlong into ſuch intricate and perplexing Non-pluſes, that they are indiſpenſably oblig’d to ſtop ſhort at the Beginning, or at leaſt in the Middle, of their Courſe.

Source: wiktionary

Being now much better able to make their queries of the secrets of that mystery, by how much their often failings had put them often to stops and non-plusses in the work […]

Source: wiktionary