Cosplay Definition Meaning Define cosplay in simple terms. Cosplay is all about dressing up and pretending to be a specific character from a manga. It has a huge sensation among fans of geek culture around the world. People diligently create outfits and props to accurately portray their favorite characters. Costume players usually participate in gatherings or cosplay events, where they can showcase their artistry and network with like-minded individuals who share the same passion. In the end, cosplay is an form of appreciation and commitment for the fictional character and a love for the nerd community.