查询结果:

n. 意外事件,事故

拆分：ac-加强意义 + -cid-降临 + -ent名词词尾 

短语: 
by accident (adv.) 偶然地

例：
A crowd soon collected at the scene of the accident. 群众迅速聚集在事故现场。
The accident hung up the traffic for several hours. 车祸使交通中断了数小时。
It was a lucky accident that we saw each other. 你我邂逅相遇,幸运之至。