1. The apparent attractiveness of a nerdy, bookwormy, down to earth girl over a hot babe because of her loyalty, personality, and ability to hang with the guys.
2. Getting turned on by a girl that is smarter than you, specifically in an instance in where she actually proves it.
1.
"I think Sarah, that girl from biology, is way hotter than suzie...but then again, it could be the Hermione Effect."
2.
Guy 1: "Dude, I was so hot for that nerdy girl from math yesterday when she was tutoring me. I mean, the way she spoke about the stuff.... it was so hot."
Guy 2: "Man, that's just the Hermione Effect"
by rubikscube95 August 14, 2011
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