Unsanity refers to a persons mental state being beyond insanity, also used as an expression when something is crazy or unbelievable.
friend: "Dude my dog just got struck by lightning....TWICE!"
you: "Unsane"
A slightly less serious version of the word insane.
Jack: You're having sex with a crocodile-human?! You're insane!
Tanya: That is too rough of a word, I am just a bit mentally unsane.