We can thank Yiddish and the wonderful cab drivers of New York City for this one.
A fool or jerk.
Dude. Do us a solid. Add your own funny insult.
Possibly the best combination of insults everyou figure it out. See also Profanity.
A dull, stupid person. A blockhead.
Someone who is weak or fainthearted.
I know it's not terribly original, but it's still fun to call someone a dick.