1.Someone who does not have the mental capacity to perform normal
human functions. Basically this person can be described as a retard.
2.Someone who is an asshole to everyone, and nobody likes them. Most
people would just call them a "dueche"; however, this person is usually
short in nature, hence the "nugget" part.
1. "Stop being a dueche nugget James and lets get going, you are always
late!"
2. "James is being an
ass, he's such a dueche nugget"