An Auckland woman is shocked after finding a racist definition of the word 'bro' in a 1997 edition of the Oxford New Zealand Dictionary.

Julia Rahui was talking with her neighbour when he brought out his copy of The Oxford New Zealand Dictionary: Words and their Origins to show her the description.

"Bro: Used by Māori young people or to or of Māori, especially among gang members, or among members of the extended family," it reads.

"One's Māori gang associates; Māori collectively (often used humorously or ironically)."

But the example given after the definition is perhaps the worst aspect.

"'Hurry up bro' - spoken to a Māori adolescent who is raping his own sister," it states.

This reportedly quotes author Bill Payne from Staunch: Inside the Gangs, a 1991 book he co-wrote.

"For example: Everyone's sitting around at gang HQ, the bro's, the prospects and even the gash. 'You scared, bro?' sneers a prospect. 'Got no balls, cuz?' says another.'"

According to Urban Dictionary, "gash" in this context refers to a vagina.