astonishment · noun U /əˈstɒn.ɪʃ.mənt/Full view
B2 very great surprise
Dictionary examples:

To my astonishment, she started laughing.

She gasped in astonishment.

Learner example:

To our astonishment, we were in front of a small house which seemed to have been built centuries ago. (First Certificate in English; B2; Greek)

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