Oxford English Dictionary (OED)

Eminem's Stan is now in dictionary

The track, from his The Marshall Mathers LP, features Dido and is about a crazed fan obsessed with the rapper.

The dictionary entry says a stan is "an overzealous or obsessive fan of a particular celebrity".

It also gives a helpful example about how it might be used. "He has millions of stans who are obsessed with him and call him a rap god.