Cover-up word used in place of negro. Refers to a person of African descent. Not really any more morally acceptable than negro, but that's okay.

Probably originated from the joke 'why are black people so tall?' - 'Because they're negroes (their knee grows)'
"You see that kneegrowth over there? I bet he's great at basketball"

- "What?"
by Skinnybit December 19, 2010
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