nonplus

"I know of many," he answered, with a smile, an answer which by its simplicity seemed to nonplus the Duke.

The renegade was a little at a nonplus, as he never had undergone the operation which he had described.

The inquiring mind is at a nonplus, and is likely to remain so.

He finds doubts and scruples better than resolves them, and has always some argument to nonplus himself.

The idea at the bottom of the piece is that the devil will carry off the wee boy if he can nonplus him.