astound

UK: /əˈstaʊnd/ US: /əˈstaʊnd/ ,(ə stound′)

WordReference Random House Learner's Dictionary of American English © 2025

as•tound /əˈstaʊnd/   v. [~ + object]

1. to overwhelm with amazement;
   astonish:
   We were astounded by this amazing feat.

WordReference Random House Unabridged Dictionary of American English © 2025

as•tound  (ə stound′), v.t. 

1. to overwhelm with amazement;
   astonish greatly;
   shock with wonder or surprise.

adj. 

2. [Archaic.] astonished;
   astounded.

• Middle English astoun(e)d, past participle of astonen, variant of astonyen to astonish 1275–1325

as•tound′ment, n. 
Synonyms

• 1. See surprise. 

Collins Concise English Dictionary © HarperCollins Publishers::

astound / əˈstaʊnd/ verb

1. (transitive) to overwhelm with amazement and wonder; bewilder

Etymology: 17th Century: from astoned amazed, from Old French estoné, from estoner to astonish