The name Dick is a boy's name of German origin meaning "dominant ruler". Dick and is often added to lists like Crazy Nicknames for Boys and discussed in our forums with posts like "Nameberry memes".
From the experts:
Dick was a once-common short form of Richard; replaced by Rick or Richie, and finally by the full name itself. Rude meaning -- make that two rude meanings -- pretty much knocks this one out of consideration.