Definition of "hairyback"

I couldn't care that the ous call me rooinek and sometimes whiterat because of my hair and face. At least I am not a hairyback I tell them.

1975, Sheila Roberts, Outside Life's Feast: Short Stories, Johannesburg: Ad. Donker, page 27

A mistake which is often made by our South African militants is to assume that we are cleverer than the police, that we can out-manoeuvre the 'hairybacks' and the 'rock spiders' […]

1986, Breyten Breytenbach, The true confessions of an albino terrorist, page 344

[…] the tyranny of the rockspiders, crunchies, hairybacks, ropes, and bloody Dutchmen. Those were the names by which we referred to Afrikaners.

1990, Rian Malan, My Traitor's Heart: Blood and Bad Dreams, page 54