Whenever my family gets together, we generally play games. Xactica, Turn the Tide, Five Crowns, Phase 10, and Coloretto are long-time favorites of the Card variety (though we also enjoy others such as Descent, Settlers of Catan, Princes of Florence, among dozens of others). Anyway, the point being that we have a very wide variety of games we play.
Recently, we've added Three Dragon Ante to the mix. It's a fun, semi-strategic, card game under the Dungeons & Dragons license. I've never played D&D much, though I have played some of the computer spin offs such as Unlimited Adventures and Neverwinter Nights. I have a reasonably thorough understanding of most D&D mechanics, though I've never been wholly invested in the property.
Imagine my surprise, then, to discover the names of two particular cards in Three Dragon Ante: Bahamut and Tiamat, the two dragon gods. These were names I had given to two of my seven Elder Dragons in THE GUARDIAN (which are also the only dragons in my series -- and there are no elves, dwarves or fairies/faeries, I swear).
I hadn't realized that these two names were used together in D&D, or I never would have chosen them to use in my own work (I picked them for their mythological significance). Fortunately it was something I caught on my own, well before the work was even sold -- how much more embarrassing would it have been to stand accused of plagiarism years later? At that stage of the game, it would have been very hard to convince anyone that the choice of name was unintentional. I hear the same sort of thing happened to Katherine Paterson with Bridge to Terebithia. I've been sympathetic to her on that issue since I first heard of it, but now I can really relate.
From now on I'll be googling every name I use if it seems at all familiar. A lot of the names I use have their roots in various world mythologies or classic works, but using names from modern writers/works isn't the same thing. I've renamed Bahamut and Tiamat to Deinderak and Tiarak, which are definitely unique. The characters were already quite unlike their (unintentional) counterparts in the D&D universe, so at least their monikers were all I had to change.
Writing a novel is an interesting endeavor in that you are simultaneously inspired by others' works and setting out to do something wholly original. The more original the better, of course, but there's no way to be original unless you know what else is out there (and, come on, good writers enjoy reading for pleasure, anyway). Sometimes a little too much of some other writer's influence sneaks into our works, and we have to guard against that. Even without the issue of plagiarism, reusing characters, names, ideas, or phrases from other works isn't going to make your own writing stand out. Where would we be if writers weren't out there inventing words like "hobbit" and "muggle" and "jedi?"