• adjective:   controlled or decreed by fate; predetermined

  Example: "A fatal series of events"

• adjective:   bringing death
• adjective:   having momentous consequences; of decisive importance

  Example: "The fatal day of the election finally arrived"

• adjective:   (of events) having extremely unfortunate or dire consequences; bringing ruin

  Example: "Such doctrines, if true, would be absolutely fatal to my theory- Charles Darwin"

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