The word stems from German and means "Body double". The word has its importance in spiritual circles, where it was believed that a person in great distress can make a hologram - even thousands of miles away. It can be a call for help, or just to connect with the family in the person's last breath in an accident.
Spiritists are actively working with this dobbelgaenger, for example during seances.
A dobbelgaenger can appear as a mist, shadow, incomplete entity or as a full-body entity, and it is reported that people are able to communicate with them.