cataract

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noun cat·a·ract \ ˈka-tə-ˌrakt \

Definition of cataract

[Middle English, from Medieval French or Medieval Latin; Medieval 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

2 a obsolete :waterspout

b :waterfall; especially :a large one over a precipice

c :steep rapids in a river

the cataracts of the Nile

d :downpour, flood

cataracts of rain

cataracts of information

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cataractous

play \ˌka-tə-ˈrak-təs\ adjective

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Examples of cataract in a Sentence

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

Recent Examples of cataract from the Web

Many physicians believe that the cardiovascular benefits derived from statins outweigh the potential risk of cataracts.

— teresa graedon, The Seattle Times, "Homemade ‘ginger ale’ calms upset stomach," 27 Aug. 2017
Keillor has survived heart surgery, a minor stroke and seizures, and recently had surgery on his left eye for cataracts and glaucoma.

— jeff baenen, idahostatesman, "Keillor still busy as he nears 75, but contemplates retirement," 4 Aug. 2017
The woman was being prepared for cataracts surgery at Britain’s Solihull Hospital when scientists discovered the lenses, according to the Washington Post.

— Fox News, "British doctors discover 27 contact lenses in woman's eye before surgery," 17 July 2017
If taken for long periods, these drops may increase the risk of cataracts and glaucoma.

— amanda macmillan, Time, "You're Treating Pink Eye the Wrong Way," 30 June 2017
Scientists aren’t sure why exercise protects against cataracts and AMD.

— robert j. davis, Washington Post, "Better sex is just one reason that exercise can be so good for you," 17 June 2017
Research shows that people who are physically active have a lower risk of cataracts.

— robert j. davis, Washington Post, "Better sex is just one reason that exercise can be so good for you," 17 June 2017
Normally, once cataracts are removed, lenses to improve vision are inserted.

— jennifer conn, akron reporter, cleveland.com, "1.5-pound Akron Zoo tamarin has successful cataract surgery," 14 June 2017
A diet high in vitamin C – oranges, red peppers, strawberries, broccoli – may help curb cataracts by 33 percent.

— candy sagon, charlotteobserver, "Protect eyes early to ward off vision loss," 9 June 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'cataract.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Did You Know?

The meaning of "cataract" we're most familiar with is also the oldest. It dates to the 14th century and comes from the Latin word cataracta, meaning "portcullis," probably because the ocular cataract obstructs vision in a way reminiscent of the way the portcullis's heavy iron grating obstructs passage into a fortress or castle. Latin cataracta has another meaning, however-"waterfall"-and that meaning gave us the water-related meanings that came in later centuries. The connection between the two Latin meanings can be seen in katarassein, the Greek source of cataracta. It means "to dash down"-an action we see in both the slamming portcullis and the cascading waterfall.