to suddenly become angry
flaring
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[T, I]~ (sth)if a person or an animal flares their nostrils(= the openings at the end of the nose), or if their nostrils flare, they become wider, especially as a sign of anger （尤指因气愤）使（鼻孔）张开，（鼻孔）张开
The horse backed away, its nostrils flaring with fear.
马向后惊退，吓得鼻翼扇动。
[I] ~ (up)(especially of anger and violence 尤指愤怒和暴力) to suddenly start or become much stronger 突发；加剧 SYN erupt
Violence flared when the police moved in.
警察逼近时爆发了暴力行为。
Tempers flared towards the end of the meeting.
会议快结束时群情激愤。flares