variolation

/ˌvɛriəˈleɪʃən/
noun
  1. The historical practice of deliberately infecting a person with a mild form of smallpox to protect them from a more severe case.
    • The practice of variolation involved introducing material from a smallpox sore into a healthy person.
    • Many people survived smallpox because of variolation, even though the method was not always safe.
    • Variolation was used in Asia and Africa long before it became common in Europe.
Synonyms
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