"Theon Greyjoy had once commented that Hodor did not know much, but no one could doubt that he knew his name. Old Nan had cackled like a hen when Bran told her that, and confessed that Hodor's real name was Walder. No one knew where 'Hodor' had come from, she said, but when he started saying it, they started calling him by it. It was the only word he had." AGOT, pg 242.
"'Hodor,' Bran agreed, wondering what it meant." AGOT pg. 582.
"'Hodor,' Bran agreed, wondering what it meant." AGOT pg. 582.