Most shredding machines are based on a revolving disc fitted with replaceable blades.

大多数粉碎机都是通过一个装有可替换刀片的旋转圆盘来工作的。

a small disc of metal.

一个小金属碟。

I had slipped a disc and was frozen in a spasm of pain.

我的一块椎间盘脱臼了，突然一阵疼痛使我动弹不得。