1 definition by WESTSIDE24

A phrase that is used mainly in the Great Brook Valley section of Worcester Massachusetts which means Drug Bust or Worcester PD. It is usually only used in Great brook valley for the MOB Outlaw gang who traffics many drugs through the city. When yelled a Gang war is usually the result. If an outsider goes into Great Brook valley and yells it, they will most likely be shot.

Even if you don't yell 5 down in Great brook valley, you still should not go into it unless you have connections.
MIke: yo I heard Joey went into Great brook valley and yelled 5 down!

Phil: Damn I hope that boys ok.

Mike: oh god no man, hes dead! He got shot by a stray bullet in the middle of a gang war!
by WESTSIDE24 July 21, 2009
Get the 5 down mug.