so surprisingly impressive as to stun or overwhelm; "such an enormous response was astonishing"; "an astounding achievement"; "the amount of money required was staggering"; "suffered a staggering defeat"; "the figure inside the boucle dress was stupefying"
Something that is astonishing is very surprising. an astonishing display of physical strength. = amazing + astonishingly aston·ish·ing·ly Isabella was an astonishingly beautiful young woman. so surprising that it is difficult to believe = amazing