mitigation

(noun) to act in such a way as to cause an offense to seem less serious. Synonyms: extenuation, palliation.

(noun) a partial excuse to mitigate censure; an attempt to represent an offense as less serious than it appears by showing mitigating circumstances. Synonyms: extenuation.

(noun) the action of lessening in severity or intensity. Synonyms: moderation. Example: "The object being control or moderation of economic depressions."