Cosplay definition of cosplay by The Free DictionaryIllustrate cosplay in simple terms. Cosplay involves dressing up and pretending to be a specific character from an comic book. This trend has immensely popular among enthusiasts of geek subculture internationally. Individuals meticulously design outfits and props that accurately reflect their favorite characters. Costume players frequently attend conventions or costume play events, where they can exhibit their artistry and connect with others who share the same passion. Ultimately, cosplay is an form of admiration and commitment for a fictional character and a love for the geek community.