Neckbeard (slang)

"Neckbeard" is a word that people use to describe guys who might have a little too much hair on their chin and neck, and who spend a lot of time playing video games, watching anime, and being really into sci-fi and fantasy stuff. They might also be a bit socially awkward and not great at talking to girls. It's not necessarily a nice thing to call someone, because it can be a way of making fun of them or suggesting that they're not cool or popular.