He was recently diagnosed with a cataract, which makes everything look blurry.

cataract 是名词，来自希腊语 kataraktes（瀑布），在医学上指"白内障"，即眼睛晶状体变得混浊导致视力模糊的病症。这个词用"瀑布"比喻晶状体混浊如同被水帘遮挡的状态。