Plural form of OU tard. OU tards are people who either attend, "graduated" from, or are big fans of the University of Oklahoma aka TardU. Oklahoma is full them of them which explains why Oklahoma isn't a desirable place.
A loud cross between a scream, a moan and a groan commonly vocalised by the retarded. Not known to have any actualy meaning but could be a possible attempt at speech.
Retard: NMMMMMMMUUGH!!!!
Person 1: WTF that was some tardscream!
Person 2: I wonder if it was supposed to mean anything.