It's like the word 'American' but used for anything that has an origin coming from the social media platform Discord or someone who spends a lot of time on said platform, gaining them the title of a Discordian, like how someone who lives in America is called American. Discordians are a wild bunch of people, all of them ranging different personality traits but you're likely to find that they're usually gamer of some sort.
Person A: Hey have you found any cool people yet?
Person B: Yeah. There's this one really hot guy who's a Discordian
Person A: Oh my god!! What a catch~