cer·ti·tude
ˈsərdəˌt(y)o͞od/
noun
- absolute certainty or conviction that something is the case."the question may never be answered with certitude"
synonyms: certainty, confidence, sureness, positiveness,conviction, assurance "the question may never be answered with certitude"- something that someone firmly believes is true.plural noun: certitudes"his certitude that “we're number one.”"