Chief rocker

From Rap Dictionary

noun

Chief Rocker

Back in the days of Busy Bee and other old school MC's, the terminology wasn't as contrived as it's become today. To be the "Chief Rocker" meant simply to be the best. If you were the best rocker (as in microphone rocker, show stopper, etc.), then you were the top man, or the Chief. "And the capital P capital M capital D-E-E's no doubt the chief rocker" -- EPMD (You Gots to Chill) [1]