What does exorbitation and speech habits mean in a phrase like this :
"...this exorbitation of discourse extends further than just the text , to encompass speech habits in general .
More context would help, but it appears to be a jargon usage indicating an a discourse that is over-exuberant. I have never met this word "exorbitation".
"Speech habits" means the individualistic ways in which people talk.
Is it a combined word (ex+orbit) meaning going out of the usual and routine way (orbit)?
Nimsnooze, although theoretically one could prefix and suffix latin based words 'until the cows come home' exorbitation is, in my opinion, an ugly and over expanded version of a sense that could be put in a much simpler way.
That aside, you seem to have answered part of your first posting by explaining the etymology of exorbitant.
Exactly!
Then , is my suggested meaning correct?
Yes.