Incident
noun
An occurrence that causes change somehow can also be called an incident.
事変 is a formal word for big, unexpected incidents that are disruptive and chaotic. This can involve natural disasters, sudden riots, or other large-scale disturbances that need military intervention. It can also refer to unannounced warfare.
You'll most likely see this word used in names for historical events, like the Manshuu Jihen (満州事変), or the Manchurian Incident. The 変 kanji suggests "change," so you know 事変 is only used for historical incidents big enough make things change!
This is a jukugo word, which usually means on'yomi readings from the kanji. If you know the readings of your kanji you'll know how to read this as well.
事変を成功させる
to successfully resolve a crisis
事変を引き起こす
to cause an incident
事変を起こす
to cause an incident
一大事変
a major incident
七七事変
the July 7 Incident (of 1937), the Marco Polo Bridge Incident
九・一八事変
the September 18 Incident (of 1931), the Liutiaohu Incident
上海事変は何年に起こりましたか。
What year did Shanghai Incident occur?
私は東京事変というバンドが好きです。
I like a band called Tokyo Jihen.
この事変は、中国では九一八事変として知られています。
This incident is known as the Mukden Incident in China.