Impressionist (entertainment)
An impressionist or a mimic is a performer whose act consists of imitating sounds, voices and mannerisms of celebrities and cartoon characters. The word usually refers to a professional comedian/entertainer who specializes in such performances and has developed a wide repertoire of impressions, including adding to them, often to keep pace with current events.
Source: Wikipedia — Impressionist (entertainment) (CC BY-SA 4.0)