Quraan is in the Standard Arabic (proper) (Fosha)
Quraan includes so powerful Arabic vocabulary which not really used in the daily life of Arabic speaking people because sadly there is no Arab country now that speaks Standard Arabic. Concerning to the pronunciation, Arabic words don't vary in pronunciation from Quraan to other texts BUT there are different schools to read Quraan, meaning u can hear a word pronounced differently from one scholar to another (they all right as far as I know).
Concerning to meanings, as u know one vocabulary may have more than one meaning which is normal, and it even happens in many texts NOT ONLY Quraan !
I hope I made this clear to you, I know I should have provided some examples but maybe I can do this later for you!
Have a good day sister :)