Unlike insanity, which is simply a lack of sanity, outsanity is the complete opposite of sanity.
Imagine going all the
way through insanity and coming out on the other end, discworld-like, in a
state that is so silly and weird and zany that there is no other way to describe it other that being completely outsane; a sort of state where your sanity is racing down
a fifth-dimension street with a soapbox parade in tow, shouting 'I am the emperor of Sicily! I am nighthoover! Fear me! FEAR ME!' - imagine that, if you can, and you might get an idea of what outsanity is like. But you have to be there to know it.