Green’s Dictionary of Slang

breker n.

also breeker
[Afk. breek, to break]

1. a tough, macho man, a fighter.

[SA] informant in DSAE (1996).
[SA]Sun. Times (Johannesburg) 2 Mar. 3: The Nationalist newspaper reported that ‘Oom Willie’ is used to tussles. He was not called ‘the breker of the north’ for nothing. [Ibid.] 7 Sept. 17: ‘Breeker’ tactics a short cut to title! [...] A breeker is South African slang for a tough guy [...] a champion street-fighter. An expression for an ou who can put the head and boot in better than the next ou [DSAE].
[SA]C. Hope Ducktails in Gray Theatre Two (1981) 46: The Brammie boys over from Joeys on their irons, and Abba’s ous, all the biggest brekers in Pretoria.
Fair Lady 21 Jan. 144: The leftover Fifties hoodlums creating the incidents were not totally cooled out... They were very heavy brekers [DSAE].
[SA]CyberBraai Lex. at 🌐 BREEKER: You probably won’t find a breeker taking afternoon tea at the venerable Mount Nelson Hotel in Cape Town. He is more likely to be found in one of those pubs where the smell of brandy overpowers even the flies who stagger out in a dazed state through the swing doors. A ‘breeker’ is a tough – someone you don’t want to mess with because his reasoning powers are unusually limited.
[SA]Mail & Guardian (Johannesburg) 6 Sept. 🌐 She a gentle soul from Durban [...] he a bulky Boksburg breker with a Jewish father.

2. a motorbike rider dressed in the classic ‘leathers’, jeans, boots etc.

[SA]cited in J. & W. Branford Dict. S. Afr. Eng. (1991).