1. to cause to be at a loss as to what to say, think, or do; perplex
Usage: formal

Examples

• The unexpected question nonplussed the candidate during the interview.
• Her calm reaction to the crisis nonplussed everyone in the room.
• The complex math problem completely nonplussed the students.
• His strange behavior nonplussed his friends and family.
• The teacher was nonplussed by the student’s unusual answer.
• The sudden change in plans nonplussed the entire team.