Synonyms of the word 
DUMBFOUNDING → ASTOUNDING - DUMFOUNDING - INCREDIBLE - UNBELIEVABLE
dumbfounding
- v. present participle of dumbfound.
astounding
- v. present participle of astound.
- adj. That astounds or astound.
dumfounding
- v. present participle of dumfound.
incredible
- adj. Too implausible to be credible; beyond belief; unbelievable.
- adj. Amazing; astonishing; awe-inspiring.
- adj. Marvellous; profoundly affecting; wonderful.
unbelievable
- adj. Not to be believed.
- adj. Incredible; so surprising it is almost unable to believe.
- adj. Implausible or improbable.
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