Conrad comes from the Old High German personal name *Conrad*, a compound of *kuon* “bold” and *rad* “counsel”. It entered English in the early modern period via German literature and the fame of several medieval rulers. Today it survives as a classic given name and a surname.
Alphonso is a personal name that entered English from Spanish and Portuguese variants of the medieval Germanic name *Alfons*. The name ultimately derives from the Germanic elements *adal* “noble” and *funs* “ready, eager”. It first appears in medieval Iberian chronicles and later spread to the English-speaking world.
“Dunce” comes from the name of John Duns Scotus (c. 1265–1308), one of the most brilliant philosophers of the Middle Ages. Renaissance humanists mocked his followers — the “Dunses” or “Dunsmen” — as obstinate pedants clinging to an outdated system. The name of a philosopher celebrated for intellectual subtlety became, through this reversal of reputation, a word for a stupid person.