Doppelgänger, the German term meaning "double walker", refers to a person who looks identical to someone else. There are several synonyms for this term, each with a slightly different connotation. A double or twin can be used to describe a literal or figurative copy of an individual, while a counterpart or alter ego implies a parallel or alternate version of oneself. A lookalike or spitting image emphasizes the physical resemblance, while a clone suggests a scientific or artificial duplication. All of these terms evoke the uncanny sensation of encountering another person who is identical to oneself, inspiring both fascination and fear.