A male fan; often derogatory, in the sense that it brings to mind some pale basement-dweller who knows more about his movie/video game/comic book "graphic novel" of choice than you, or indeed their creators, could ever hope to. Example: Comic Book Guy. Interestingly, I've never heard it used as a verb (unlike fangirl), nor have I heard it used very often in a positive sense (again, unlike fangirl).

• Glossary