Something one (usually a camp drip of a wimp) says when they've had enough of being fucked around with. Usually followed by racially motivated attack on a minor, perpatrated by said camp drip of a wimp. Alternate forms include "You need slapping down." and "You, my dear boy, are in need of a good spanking in the downward direction."
In the garage, Jordan calls Ben Mitchell a sap (he meant to say puff but Eastenders is supposedly "family viewing". Hah!)

Ben was pissed off, so much so that he could've even said Bubbly's in the fridge . But instead, Ben picked up the wrench menacingly and wailed "You need slappin dahn!" before opening the proverbial can of whoop ass on Jordan.
by Mons†er August 24, 2011
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