Someone who clearly likes to over indulge in the partydrug GHB GBH. When taking in excess the user often experiences incontrollable body movements, makes random noises and yelling offensive obsenities at total strangers as if they have severe tourettes syndrome.
Dan: Hey, looks like Jimmy's over done it on the GHB again.
Megan: Clearly, I can see his manky arms flapping about like that retard window licker from bach in school.
Dan: He's with out a doubt the biggest G-tard i've ever met!
someone that thinks they are being funny when really they are not, it helps if they think they are a funny gangster type but really are just some lame ass suburban nerd like the guy that sent in the definition for g rated pregnancy.
Have you read the definition for g rated pregnancy on urban dictionary.com its g tarded and so is guy that sent that in!