dumfound

dʌmˈfaʊnd

verb

greatly astonish or amaze.

I was dumbfounded by the low prices there

astonish,astound,amaze,stagger,surprise,startle,stun,confound,stupefy,daze,nonplus,throw,shake,unnerve,disconcert,discompose,bewilder,take someone’s breath away,take by surprise,take aback,shake up,stop someone in their tracks,strike dumb,leave open-mouthed,leave aghast,catch off balance,flabbergast,floor,knock for six,knock sideways,knock out,knock the stuffing out of,bowl over,blow someone’s mind,blow away,astonished,astounded,amazed,staggered,surprised,startled,stunned,confounded,nonplussed,stupefied,dazed,dumbstruck,open-mouthed,agape,speechless,at a loss for words,thunderstruck,goggle-eyed,wide-eyed,taken aback,thrown,shaken,unnerved,disconcerted,discomposed,bewildered,flabbergasted,floored,flummoxed,knocked for six,knocked sideways,knocked out,bowled over,blown away,gobsmacked