big willie, n. — Green’s Dictionary of Slang

big willie n.

[SE big + generic use of proper name; + ? willie n.⁵; see cit. 1996]

(US black) a sophisticated, successful urban black male.

1996		Vibe Sept. n.p.: The Big Willie [is] the strong, silent type [...] an old-school romantic (and) a savvy businessman [...] a free thinker, fluent with modern technology. He is fearless, vigilant and innovative.
2002		‘Touré’ Portable Promised Land (ms.) 55: Here they are: the dialect’s heavyweight champeens. The soul semiotics HNICs. The vernacular’s Big Willies.