Definition - Noun : a circumstance relating to the commission of an act that increases the degree of liability or culpability <punitive damages are recoverable in a conversion case when the evidence shows legal malice, willfulness, insult, or other aggravating circumstances Schwertfeger v. Moorehouse, 569 So. 2d 322 (1990)> also : a circumstance (as lack of remorse) relating to an offense or defendant that receives consideration by the court esp. in imposing a death sentence compare mitigating circumstance