The Batman Adversary is the JOKER, a five-letter word. The JOKER is a supervillain and archenemy of the superhero Batman. He first appeared in Batman #1 in 1940 and has been a recurring character in the DC Comics universe ever since. He is known for his green hair, white skin, and maniacal laughter. He is often portrayed as a criminal mastermind and is considered one of the most iconic and recognizable villains in popular culture.