astounder

noun

1. A person who astounds.

   “[…] while waiting for my interview at Government House, I had been dazzled by two most gorgeously-apparelled Rajahs, who went in before me; and as I heard that the Viceroy was to have a farewell garden party on Friday, the 7th of December, I was most anxious to see […] a crowd of these astounders.”

   “I am an educator of the young, not an astounder of the old; and it is for the boys and girls who read my book that I thus point the morals that life’s tale has taught me.”

   “1970, Francis Steegmuller, Cocteau: A Biography, Boston: Little, Brown, Chapter 3, p. 88, […] the insecurity that made Diaghilev’s command important to him permeated his achievement with the compulsion to astound and to associate himself with astounders.”

2. A thing or occurrence that astounds.

   ““My dear France,” he says, holding both her hands, “this is an astounder. We knew you were coming, but not so soon. When did you arrive, and where are you located?””