Someone who constantly repeats the same lame joke they've already told you 3,000 million times before, expecting that the 3,001 millionth time you're bound to laugh.
Retarded Monkey Fuck: Hey, what's brown and sticky?
Other Guy: I don't know, jackass. Why don't you tell me?
Retarded Monkey Fuck: A stick! Haha!
Other Guy: I'm so glad I have zoloft...
Its not self-explanitory, it occurs when there is either an incest relationship because they did not spread apart the genes, therefor resulting in a shallow gene pool.
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.