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1. To act in such a way as to cause an offence to seem less serious
   - extenuation, palliation
    
2. A partial excuse to mitigate censure; an attempt to represent an offence as less serious than it appears by showing mitigating circumstances
   - extenuation
    
3. The action of lessening in severity or intensity
   "the object being control or mitigation of economic depressions";
   - moderation

Derived forms: mitigations

Type of: alibi, decrease, diminution, exculpation, excuse, reduction, self-justification, step-down

Encyclopedia: Mitigation