astounding
1. [ adjective ] bewildering or striking dumb with wonder
Synonyms: dumfounding dumbfounding
Related terms: incredible
2. [ adjective ] so surprisingly impressive as to stun or overwhelm
Synonyms: staggering stupefying astonishing
Examples:

"such an enormous response was astonishing" "an astounding achievement" "the amount of money required was staggering" "a staggering defeat" "the figure inside the boucle dress was stupefying"

Related terms: impressive
Similar spelling:   astound
  astounded
  astonishing
  astonishingly
  astonish
  astonied
  astonished