1). The feeling one gets when scratching a long-running, very annoying itch. This usually applies to situations where the itchy person is in a public place for an extended period of time, and the itchy area is one generally not considered polite to scratch in public. Also applies to places where the person cannot reach to scratch, such as the middle of the back. Can also be referred to as an itchgasm.
Guy: Arg, I can't reach that itchy spot on my back!
Girl: I'll get it.
*Girl scratches itchy part of back
*Guy moans, in the middle of an itchasm
The term "itchassness" is slang term for when you have a badcase of itchy ass. itchassness broke out as a wide-spread epidemic catch phrase, and has been played out, forgot about and played out again throughout the states.