Wiktionary
get outta here
interj. 1 (eye dialect of get out of here English) 2 (context colloquial English) Used to tell somebody to go away or leave one alone. 3 (context idiomatic colloquial English) Indicating disbelief or requesting confirmation.
Usage examples of "get outta here".
We hafta get the wounded back t'the cillas and get outta here before The Hook changes his mind and builds his fire up here.