OEDCD is the name for a mental disorder characterized by the compulsive need to look things up in the Oxford English Dictionary (OED). The disorder is common among English graduate students. It is related to, but not always associated with, Obsessive Compulsive Disorder (OCD). The acronym stands for Oxford English Dictionary Compulsive Disorder.
Ryan's OEDCD got to the point where he wouldn't leave the house anymore, even for school, work or social engagements, because there was always one more word to look up in the OED. "Are you doing OK?" his roommate asked. He responded, "'OK!' How have I not looked 'OK' up in the OED?! Wait, it says here the first use was in the 1800s, and the etymology..."