Green’s Dictionary of Slang

(US teen) a derog. term for an intellectual, bookish person.

1981		Eble Campus Sl. Mar. 5: poindexter – person, usually a male, who studies all the time.
1997–2000		Da Bomb 🌐 22: Poindexter: Nerd.
2008		‘Grandmaster Flash’ Adventures 181: Joseph was that nerdy poindexter who gave everything else up for the things he loved.
2013		T. Pluck ‘Story of O Street’ in Life During Wartime (2018) 55: They looked like kids he’d called poindexters in high school, except they didn’t seem to know they were nerds.