Definition: A return of a behavior or trait after it hasn’t been observed for a period of time
Part of Speech: Noun
Synonym(s): regression, relapse
1. In biology, the teacher explained how atavism is the reoccurrence of a particular trait after a number of generations.
2. The fashion world displays its atavism when it turns an outdated style into a current trend.
3. Since Mark had been sober for twelve years, his return to drinking reflected a much unwanted atavism.