Quixotic fellow? (3)
I believe the answer is:
don
'fellow?' is the definition.
(both can mean an academic)
I don't understand the remainder of the clue.
Can you help me to learn more?
(Other definitions for don that I've seen before include "Mafia chief or Spanish title" , "Put on; lecturer" , "- - Giovanni, 26" , "Mafia boss" , "Spanish male title" .)