動揺 ― rock

”岩”のロックではなく、”揺らす”方の"rock"です。

物理的に対象を激しく揺らす、振動させるという意味もありますが、事件や事象のインパクトが多大で、（心理的に）動揺が拡がっている、というような場合にも用いられるようです。

中国で、男が子供と教師を学校内で刃物で襲い、殺してしまったという事件があり、動揺が拡がっています。

China rocked as man kills seven children, teacher

A MAN hacked seven children and their teacher to death with a meat cleaver yesterday, in China's latest bloody schoolyard rampage. It was the eighth brutal attack on children in 10 weeks.

Yesterday, Wu Huanmin, 48, massacred five boys, two girls and their kindergarten teacher, and wounded 20 others, before returning to his Shaanxi province home and killing himself, according to Xinhua.

''There was blood everywhere,'' a local man named Zheng Xiulan said after witnessing the kindergarten scene. ''I don't know why he did it … I hadn't heard that he was mentally ill. He wasn't poor either.''
(The Age. May 13, 2010.)