Someone who is not quite attractive enough to be called "hot" and not quite ugly enough to be called "fugly." Usually takes more than a first impression for you to see their real beauty.
Friend 1: "Damn, I met Dante's new girl the other night..."
Friend 2: "the one he met at the Library when he was checking out that book on stds?"
Friend 1: "Yea, she's a real think piece"
Friend 2: "Word"