The definition of certitude means absolute confidence in something or an unquestioning belief in something.
(noun)People who are very religious express certitude about their faith.
See certitude in Webster's New World College Dictionary
noun
Origin: OFr < LL(Ec) certitudo < L certus, certain
See certitude in American Heritage Dictionary 4
noun
Origin:
Origin: Middle English
Origin: , from Late Latin certitūdō
Origin: , from Latin certus, certain; see certain
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