CATARACT

noun Etymology: Latin ~a waterfall, portcullis, from Greek kataraktēs, from katarassein to dash down, from kata- + arassein to strike, dash Date: 14th century a clouding of the lens of the eye or of its surrounding transparent membrane that obstructs the passage of light, 2. waterspout , waterfall , steep rapids in a river, downpour , flood , ~ous adjective