You searched for: “avouchment
avouchment (s) (noun), avouchments (pl)
1. Statements asserting the existence or the truth of something: Shirley made a strong avouchment that she had nothing to do with the fight that took place at the party which involved her brother and another guy.
2. Declarations made emphatically; as if no confirming evidence is necessary: The avouchment made by the weather forecaster that it would rain that day was accepted by everyone because that is exactly what was going on!