A social outcast is somebody who is not involved in social events and spends way to much time doing a "hobby". Hacking computers, dealing drugs, trying to make friends over the internet or mabye playing tennis with "mummy". There are many different social outcasts but the traditional one is the one who always looks slightly high or depressed all the time. Many are alone because they have been singled out as a "freak" by a popular bitch and nobody has a mind of there own to judge. Sometimes they are merely too snobbish and see themselves as above everyone else although this is sometimes just to hide there feelings. Sometimes they are alone because they want to be.
'Jenny's gone round the back again, I swear she's not stable, she's such a total social outcast.'