An occurrence or event — something that happens; can refer to everyday happenings or notable incidents.
昨日の出来事について詳しく教えてください。
Please tell me in detail about what happened yesterday.
小さな出来事でも人の心に残ることがある。
Even small events can remain in a person's memory.
その事故は予想外の出来事だった。
That accident was an unexpected event.