stumper

[ stuhm-per ]
/ ˈstʌm pər /

noun

a person or thing that stumps.
an extremely difficult question, task, or problem.
a person who makes stump speeches.

Origin of stumper

First recorded in 1725–35; stump + -er1
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

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