From Longman Dictionary of Contemporary Englishastoundas‧tound /əˈstaʊnd/ verb [transitive] SURPRISEDto make someone very surprised or shocked SYN astonish The judge’s decision astounded everyone. It astounded me that she succeeded.→ See Verb table
Examples from the Corpus
astound• Turner's business sense continues to astound me.Origin astound (1300-1400) Probably from the past participle of astone; → ASTONISH 