Green’s Dictionary of Slang

righteous adv.

[righteous adj.]

(US black) absolutely, completely.

[US]P. Crump Burn, Killer, Burn! 242: Cool yourself into rigor mortis for not copping righteous on de gismo when you had it on de slaughtering floor.
[US]O. Hawkins Ghetto Sketches 70: I knew some cats who converted and they sho’ ’nuff righteous got they shit together.
[US]R. Price Freedomland 104: We’re gonna be great, man... We’re gonna do it righteous.