Cataract (noun)

1. A medical condition in which the lens of the eye becomes opaque, resulting in cloudy or blurred vision.
2. A large, powerful waterfall or a similar natural phenomenon.

Origin:

From latin cataracta, from ancient greek κατάρακτος (katáraktos, "waterfall, cataract").

Examples:

1. He had surgery to remove the cataract from his eye.
2. The cataract caused her vision to become blurry and cloudy.
3. The Niagara Falls is a famous cataract.
4. The cataract in the river was a popular spot for rafting and kayaking.
5. The cataract was a spectacular sight, with the water crashing down from a great height.