"No Police"

It appears to be a localized hybrid of 54 and 50 or fifty. It combines definitions of 54 (police radio lingo for 'no') and 50/Fifty (the slang term for police, as in "The 5-0", "Hawaii 5-0", or "the Fifty") to make "54-50" (pronounced "Fifty-four Fifty"). I keep hearing this term interspersed/interjected into the lyrics of local gangsta rap here in Baltimore.
"Bitches and niggas git outta my face (fifty-four fifty....) dis is my crib, gonna bust your face (fifty-four fifty...)"
by jtimleck August 11, 2008
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