n.[U][C]

1. 動亂；動盪；騷亂；激變；劇變
   Mass unemployment may lead to social upheaval.

   大批失業會導致社會動亂。

   The death of the King caused political upheaval in the country.

   國王逝世造成政局的動盪。

2. 脹起；鼓起；舉起；（地殼）隆起

n.

1. a violent or sudden change or disruption.
2. an upward displacement of part of the earth's crust.