variolization vs variolation

variolization and variolation both are nouns.

Word	Noun	Adjective	Verb	Adverb
variolization	Yes	No	No	No
variolation	Yes	No	No	No

As nouns, variolization and variolation are synonyms defined as:

variolization and variolation: the obsolete process of inoculating a susceptible person with material taken from a vesicle of a person who has smallpox

variolization (noun)	variolation (noun)
the obsolete process of inoculating a susceptible person with material taken from a vesicle of a person who has smallpox	the obsolete process of inoculating a susceptible person with material taken from a vesicle of a person who has smallpox