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1.
a person who takes large ammounts of class A drugs, more specifically heroin. These people are easily recogniseable by the clothes that they wear and their stench due to them selling every possesion to get more heroin.
that lad is a bad scag head laaaa
by fatboy April 13, 2004
 
2.
Usually means somebody you don't like you refer to them as 'Scag heads'. Tramp, ugly, unpretty, nasty, unpleasant.
'Look at dat scag head over dere'
by *~*Bird*~* October 30, 2005