Any food which is made by a retard but is still quite tasty.Or alternatly any food made by someone with poor culinary skills and the food looks like it is suffering from some kind of physical deficiency.
Someone (or something) that overtly appears to be retarded, however, upon closer inspection, appears to be awesome. May be applied to something so stupid that it is cool.
"That girl over there is an idiot, but I heard she is easy...she's so retardicious."
"That girl at the other table is a total pig, but shes hot... pretty retardicious."
When you fail at something in life (eg. failing an exam or not getting a job), go home and spend an hour just standing in the shower, propping yourself up against the wall with your eyes on your feet.
Caleb knew the only thing to do after he didnt get prefect was take a failure shower.