/dis-kor'di-*n-ism/
n. The veneration of Eris, a.k.a. Discordia; widely popular among hackers. Discordianism was popularized by Robert Anton Wilson's 'Illuminatus!' trilogy as a sort of self-subverting Dada-Zen for Westerners -- it should on no account be taken seriously but is far more serious than most jokes. Consider, for example, the Fifth Commandment of the Pentabarf, from 'Principia Discordia': "A Discordian is Prohibited of Believing What he Reads." Discordianism is usually connected with an elaborate conspiracy theory/joke involving millennia-long warfare between the anarcho-surrealist partisans of Eris and a malevolent, authoritarian secret society called the Illuminati.
See appendix B, Church of the SubGenius, and ha ha only serious.