perniciousanother word for 'bad' meaning having a harmful effect, especially in a gradual wayThe pernicious influence of misinformation on public opinion cannot be underestimated.NoteThe pernicious influence of misinformation on public opinion cannot be underestimated.Elon.io is an online learning platformWe have an entire course teaching IELTS Vocabulary — Band 7+ grammar and vocabulary.Start learning IELTS Vocabulary — Band 7+ now