1. to have all three forms of mental retardation (hence tha trey)
2. Political figures, of obvious mental short comings (right or left)
3. Somone so dense, so stupid, they the actually seem to be retarded, but are infact not retarded (but you swear they are)
Example 1; Billy is a treytard, and goes to special education, he rides the short bus to school
Example 2; Sarah Palin is such a Treytard, she thinks because she was a in a beauty pagent she can be a good presidential candidate, because the Repulican party doesn't have anything going for themselves
Barry Obama is going down in history as one of the biggest treytards in history, the guy has no concept of how taxes and spending money works, and will screw a next generation buy his bad decisions.
Example 3; Bob got fired from McDonalds, because he couldn't read the menu and was always screwing around, what a treytard.