A CoDtard is a person of lesser intellectual capacity than the average human, this leads to an uncanny addiction to the Call of Duty series. A CoDtard can't motivate why they like Call of Duty or why it is superior to other games, in their opinion. Most CoDtards are also trolls on other game forums. CoDtards are often also white-supremacists. Most CoDtars are in the age group 9-15, tough some rare exceptions are known to exist.
CoDtard: The Halo: Reach graphics look like shit.
Human 1: Have you even seen them?
CoDtard: Why would I waste my time on shit like that?!
Human 2: Seriously you can't just say everything that isn't made by Infinity Ward or Treyarch is shit.
CoDtard: Shut up you niggers!!!
The Call of Duty syndrome is a serious disease caused by the Call of Duty series(A game series developed by some homophobic homosexuals somewhere). It's a state of delusionary paranoid outbursts. The species CoDtard are most vulnerable to the disease.
A few good examples of events that can trigger an outburst:
-An airplane flying by
-A person sprinting towards the person with the syndrome
-Meeting a Russian
-Meeting a German
-Hearing a loud noise
These events can lead to extremely violent behavior from the person with the Call of Duty Syndrome.