Simple past tense and past participle of astonish.(verb)
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Use "astonished" in a sentence
"Most Europeans are astonished at the rapidity with which the Americans despatch their meals; but I, having admitted the proposition, that there was "nothing new under the sun," had long previously ceased to be _astonished_ at any thing."
"The word astonished literally means, “struck dumb with amazement.”"
"The revelation was made all the more remarkable by its tim ing: only a few years after Donald Griffin astonished the scientific community in 1958 with his revelation that bats "see" the world with their ears."