flare-up
noun [ C usually singular ] uk/ˈfleə.rʌp/ us/ˈfler.ʌp/
（暴力、疼痛或愤怒）爆发，突发，加剧
a situation in which something such as violence, pain, or anger suddenly starts or gets much worse
There was another flare-up of rioting later that day. 那天晚些时候再度爆发骚乱。
Synonym: outburst