staggering

Adjective

• 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
    

Related words

• Synonyms: 
  astonishing , astounding , stupefying