1. [adj]  shocking with surprise and consternation; "the stupefying impact of the tragedy"
2. [adj]  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"
3. [adj]  making physically stupid or dull or insensible; "a stupefying blow to the head"; "the stupefying effects of hemp"

STUPEFYING is a 10 letter word that starts with S.