noun \ˈka-tə-ˌrakt\

medical : a condition in which a part of your eye (called the lens) becomes cloudy and you cannot see well

: a large waterfall

Full Definition of CATARACT

[Middle English, from Middle French or Medieval Latin; Middle French catharacte, from Medieval Latin cataracta, from Latin, portcullis] :  a clouding of the lens of the eye or of its surrounding transparent membrane that obstructs the passage of light
a obsolete :  waterspout
b :  waterfall; especially :  a large one over a precipice
c :  steep rapids in a river
d :  downpour, flood <cataracts of rain> <cataracts of information>
cat·a·rac·tous \ˌka-tə-ˈrak-təs\ adjective

Examples of CATARACT

  1. <the roaring cataract is one of the park's most majestic sights>
  2. <in spring the melting snows usually produce a cataract that inundates the valley>

Origin of CATARACT

Latin cataracta waterfall, portcullis, from Greek kataraktēs, from katarassein to dash down, from kata- + arassein to strike, dash
First Known Use: 14th century

Related to CATARACT

cascade, waterfall, fall(s)
drought (also drouth)

Other Geology Terms

anthracite, boulder, cwm, erratic, igneous, intrusive, mesa, sedimentary, silt, swale


noun \ˈkat-ə-ˌrakt\   (Medical Dictionary)

Medical Definition of CATARACT

: a clouding of the lens of the eye or its surrounding transparent membrane that obstructs the passage of light


noun    (Concise Encyclopedia)

Opacity of the eye's crystalline lens. Cataracts causing central visual-field defects are most likely to affect vision. Cataracts may occur in newborns and infants. Diabetes mellitus, prolonged exposure to ultraviolet rays, or trauma can cause them in adults, but they most often occur with age, resulting from gradual loss of transparency of the lens. Treatment is a surgical procedure to replace the lens with an artificial one.


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