Final answer:
Hypermature cataracts are a very advanced stage of cataract development, where the lens of the eye becomes completely opaque and hard, leading to severe vision loss or blindness.
Step-by-step explanation:
Hypermature cataracts refer to a very advanced stage of cataract development in which the lens of the eye becomes completely opaque and hard. At this stage, individuals may experience severe vision loss or blindness. The cloudiness of the cataract prevents light from passing through the lens and reaching the retina, resulting in blurred or distorted vision.