deadly applies to an established or very likely cause of death.
a deadly disease
mortal implies that death has occurred or is inevitable.
a mortal wound
fatal stresses the inevitability of what has in fact resulted in death or destruction.
fatal consequences
lethal applies to something that is bound to cause death or exists for the destruction of life.
lethal gas
Example Sentences
a disease that is often fatal a chemical that can be fatal to birds She made a fatal mistake.
Recent Examples on the WebPolio vaccines are 99% effective against paralytic polio, which can be fatal in 2% to 10% of cases. Aria Bendix, NBC News, 9 Sep. 2022 In the worst case, giving your dog Ibuprofen or Tylenol could be fatal, says rover.com. Olivia Munson, USA TODAY, 8 Sep. 2022 Traditionally, pickers wearing spiked shoes climb the trees -- which can grow to 20 meters (about 65 feet) -- and falls can be fatal. Kathleen Magramo, CNN, 8 Sep. 2022 Several maulings have been reported in the Anchorage area this year, including one on Joint Base Elmendorf-Richardson in May that was fatal. Tess Williams, Anchorage Daily News, 8 Sep. 2022 That combination of high heat and humidity is potentially fatal, scientists say. Insiya Syed, WSJ, 6 Sep. 2022 Although most people recover from Legionnaires' with antibiotics, certain patients -- including those who are immunocompromised or who suffer from chronic lung diseases -- can develop complications that can be fatal. Mary Kekatos, ABC News, 5 Sep. 2022 Police arrived at 10124 Whispering Pines and found Daniel Felton, 65, of South Madison, Miss., in the driveway with a gunshot wound that proved to be fatal. Grant Lancaster, Arkansas Online, 5 Sep. 2022 The Lancet Infectious Diseases in 2019, reported that among 122 cases there, seven had been fatal. Andrew Joseph, STAT, 1 Sep. 2022 See More
Word History
Etymology
Middle English, from Latin fatalis, from fatum fate