exacerbation

pos>n. [ Cf. F. exacerbation. ] 1. The act of rendering more violent or bitter; the state of being exacerbated or intensified in violence or malignity; as, exacerbation of passion. [ 1913 Webster ]

2. (Med.) A periodical increase of violence in a disease, as in remittent or continuous fever; an increased energy of diseased and painful action. [ 1913 Webster ]