I'm amazed at how many need to diagnose their horse's nature and to such an extent. My one horse is a bone head, now that might not tell you folks much but I was raised with that expression and it certainly sums up the horse's nature to me. And I know lots of fine horsemen who fully grasp it's meaning.
This is also a really cool website that has some more horse personality descriptions. Horse Personalities Descriptions This one is based on the following traits... Dominant or Submissive Energetic or Lazy Curious or Afraid Friendly or Aloof