An increase in the severity of something (such as a disease)(noun)
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Use "exacerbation" in a sentence
"A significant worsening of symptoms - called an exacerbation - can last several weeks and often requires substantial medical intervention, including hospitalization."
"A significant worsening of symptoms called an exacerbation can last several weeks and often requires substantial medical intervention, including hospitalization."
"I believe that few Canadians, other than old pols who have done nicely under the undemocratic FPTP, and their political and media hangers-on, truly prefer minority rule and wasted votes and hyper-partisanship and the exacerbation of regional differences, all of which are fostered by the current system."