1. to shock or surprise someone so much that they cannot speak or react
Usage: also spelled ‘dumbfound’

Examples

• The magician’s trick completely dumfounded the audience.
• She was dumfounded by the unexpected news of her promotion.
• The complexity of the math problem dumfounded even the brightest students.
• His rude behavior dumfounded everyone at the dinner party.
• The sudden change in weather dumfounded the meteorologists.
• I was dumfounded when I discovered the truth about what happened.