Surprised, amazed, astonished or bewildered.(adjective)
Wiktionary.org : Text is available under the Creative Commons Attribution-ShareAlike License
Use "astounded" in a sentence
"Yes, I am plain astounded that they like the idea of being on the air together. —"
"Most of it is a defence of Sappho's chastity, which some German had denied, and I can assure you the passion with which these two gentlemen argued, the learning they displayed, the prodigious ingenuity with which they disputed the use of some implement which looked to me for all the world like a hairpin astounded me; especially when the door opened and Professor Hobkin himself appeared."
"When at last he raised his head, his expression astounded me."