The Collaborative International Dictionary of English v.0.48:

Hoodlum \Hood"lum\, n.
   A young rowdy; a rough, lawless fellow; colloquially, called
   also hood. [Colloq. U.S.]
   [1913 Webster]

         Just tell your hoodlum friends outside
         You ain't got time to take no ride. --Yakety-Yak (Song)
   [PJC]

WordNet (r) 3.0 (2006):

hoodlum
    n 1: an aggressive and violent young criminal [syn: hood,
         hoodlum, goon, punk, thug, tough, toughie,
         strong-armer]