Atavist, which means a person or thing that embodies or displays ancestral traits or characteristics, has several synonyms. One of them is throwback, which refers to something exhibiting traits of a previous era. Another synonym is reversion, which denotes a return to an ancestral or previous condition or state. Retrogression is another synonym for atavist and refers to a decline or regression to an earlier state. Lastly, ancestral is another word that can be used in place of atavist, which means relating to or inherited from an ancestor or earlier period. All these synonyms have a common theme, which is going back or returning to something from the past.