Source : Webster's Revised Unabridged Dictionary (1913)

Variolation \Va`ri*o*la"tion\, n. (Med.)
   Inoculation with smallpox.

Source : WordNet®

variolation
     n : the obsolete process of inoculating a susceptible person
         with material taken from a vesicle of a person who has
         smallpox [syn: {variolization}]