1.) Someone who tries to be something that they are not
2.)Teenage boys (usually white or asian) who have Justin Bieber-style or closely shorn hair or fauxhawks, wear designer super-skinny jeans, designer skate shoes, and "vintage"-style shirts showcasing bands that they do not know about nor give a shit about (just trying to look cool). Usually seen trying to poser-jerk to shitty mainstream rap or hanging with their scene cunts, trying to look "gangsta".
Seen usually in rich, white areas.
Poser: (in fake gangsta drawl) Fuck you, faggot! They're a band. (gives scene cunt a lecherous stare and pulls his skinny jeans down some more)
Teen 2: You're just an insecure asshole who has nothing better to do than put people down because you're scared of what will happen to you in the future.
Teen 1: What?