lethalsufficient to cause death; used especially of doses, injections, and weapons ("a _____ dose")An overdose of certain medications can be lethal if not treated immediately.NoteAn overdose of certain medications can be lethal if not treated immediately.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