confirmation

(noun) additional proof that something that was believed (some fact or hypothesis or theory) is correct. Synonyms: verification, check, substantiation. Examples: "Fossils provided further confirmation of the evolutionary theory."

(noun) information that confirms or verifies.

(noun) making something valid by formally ratifying or confirming it. Synonyms: ratification. Examples: "The ratification of the treaty." "Confirmation of the appointment."

(noun) a ceremony held in the synagogue (usually at Pentecost) to admit as adult members of the Jewish community young men and women who have successfully completed a course of study in Judaism.

(noun) a sacrament admitting a baptized person to full participation in the church.