noun
dunce
DUNS/dʌns/
A person regarded as stupid or slow to learn.
He feels like a dunce when he forgets simple instructions.

Etymology
Duns first identified followers of the scholar John Duns Scotus. Opponents turned their name into an insult for hairsplitting or obstinate thinkers, which then broadened to a dull-witted student.
In context
He's just kind of a big dunce about it.
More examples
- Getting one answer wrong doesn't make you a dunce.
- She plays the class dunce to make her friends laugh.
- The teacher refuses to call struggling students dunces.
Forms
dunce · dunces