denigrate

/ˈdɛnɪɡreɪt/
verb
  1. To criticize someone or something unfairly; to say that someone or something is not good or important.
    • The politician tried to denigrate his opponent's record during the debate.
    • It's not fair to denigrate someone's hard work just because you disagree with them.
    • She felt that the review denigrated her entire career as a teacher.