This might sound a little silly I know, but there is a game called Tomb Raider 2, which contains an artifact called the Dagger of Xian. No explanation is given in the game for the name. I have looked at Wikipedia for examples of "Xian" , and apart from places in China, Xian can also refer to "immortality" or "higher being". I'm not sure if the developers of the game just chose a Chinese sounding name at random, or if they had done a bit of research into the deeper meanings behind the name. In the game, anyone plunging the dagger into their heart will turn them into a dragon, almost impossible to kill. Which does actually fit the "immortal" meaning of the word.
I know Tomb Raider is just a video game but it actually got me interested in Chinese language and culture!