The word "doppelganger" refers to a non-biologically related look-alike or double of a living person. It is often used to describe a person who closely resembles another person, sometimes implying an eerie or supernatural quality. The term can also be used in a more playful or casual context to talk about someone who shares similar characteristics or features with another individual.
The term "doppelganger" comes from the German words "doppel," meaning "double," and "gänger," meaning "walker" or "goer." The combination thus translates to "double walker." It first emerged in the 19th century but has its roots in folklore where a doppelganger was often seen as an omen or a harbinger of bad luck.