Green’s Dictionary of Slang

(S.Afr.) a gangster, a streetwise individual.

1963		Wilson & Mafeje Langa 22: The townees or tsotsis are also called ‘location boys’, ooclever, bright boys, and spoilers, after a gang which terrorized Alexandra Township in Johannesburg.
1971		M.O. Mtshali ‘The Detribalised’ in Chapman & Dangor Voices from Within (1982 ) 74 : He’s a ‘clever’ / not a ‘moegie’; / he never say baas / to no bloody white man.
1977		F. Dike First South African 4: That’s a small time clever. He thinks he’s going to jive me, but he forgets that I have heard this story. [Ibid.] 12: He says they’re clevers and they’re dangerous.
1987		M. Melamu Children of Twilight 91: Ek se, clever, who have you been writing to?
1990		J. Naidoo Coolie Location 214: But the tough ‘boys’ of the Depot, the clevas, dissuaded the potential mavericks with a sharp look.
2000		(ref. to 1940s) C. Glaser Bo-Tsotsi 49: In Johannesburg, a more generic term for young township ‘city slickers’ was ‘clevers’.