Citations:Harry Potterdom

Noun: "the fandom or sphere of the Harry Potter series and the movies based on it"

 * 2007, Sue Upton on December 2007 episode of, quoted in E. A. Pyne, The Ultimate Guide to the Harry Potter Fandom, What the Flux Comics Publishing (2010), ISBN 9781450745604, page 108:
 * Although squee and its use has been around for some time now, I like to think that this decidedly once-uncool word or expression is now accepted among the many fans in the world of online Harry Potterdom.
 * 2008, Melissa Anelli, Harry, A History, New York: Pocket Books, ISBN 1416554955, chapter 10, :
 * As we had just spent years salivating for new canon—that is, new information about the books straight from Jo—in the lull between books fanfiction writers who wrote long and epic pieces were starting to be considered something like demigods in Harry Potterdom.

Noun: "the fictional universe which is the setting of the Harry Potter series"

 * 2005, Jax Peters Lowell, The Gluten-Free Bible: The Thoroughly Indispensable Guide to Negotiating Life without Wheat, Henry Holt and Company, LLC, ISBN 0805077464, part 4, chapter 14, :
 * There is no better time to invoke your right to tell a little white lie than on Halloween, where a well-meant treat can turn into a nasty trick for your gluten-challenged vampire, fairy princess, or denizen of Harry Potterdom.