cataract

noun
cat·a·ract | \ˈka-tə-ˌrakt \

Definition of cataract 

1 [ 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

2a 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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Other Words from cataract

cataractous \ˌka-tə-ˈrak-təs \ adjective

Synonyms & Antonyms for cataract

Synonyms

bath, cataclysm, deluge, flood, flood tide, inundation, Niagara, overflow, spate, torrent

Antonyms

drought (also drouth)

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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.

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 on the Web

Cataract surgery is performed to treat cataracts, which can cause blurry vision and increase the glare from lights. Dave Quinn, PEOPLE.com, "Princess Charlotte Is Once Again the Queen's Mini-Me in Adorable New Shades: See the Photos!," 12 June 2018 Alcon also manufactures medical devices, particularly those used in eye surgeries such as procedures for treatment of cataracts, as well as laser eye surgery. Gordon Dickson, star-telegram, "No need to shed tears yet. Alcon promises to stay in Fort Worth after spinoff," 9 July 2018 Exposure can cause an array of health problems, including cancers, cataracts and digestive ailments. New York Times, "Decades Later and Far Away, Chernobyl Disaster Still Contaminates Milk," 8 June 2018 When the ozone layer is weakened, more UV rays can get through and affect humans, making them prone to skin cancer, cataracts and other diseases. James Griffiths, CNN, "Ozone-destroying emissions are on the rise and scientists don't know why," 16 May 2018 The zeaxanthin is protective against cataracts and macular degeneration. Sheah Rarback, miamiherald, "Ubiquitous mangos taste good - and are good for you, too," 29 June 2018 Photographer: Manaure Quintero/Bloomberg A cataract of confetti almost obscures Maduro at a rally in Caracas. Philip Brian Tabuas, Bloomberg.com, "Venezuela Votes in a Presidential Election. Enthusiasm Is Absent," 19 May 2018 When that stops working, the only way to cure cataracts is surgery, the Mayo Clinic says. Korin Miller, SELF, "6 Weird Reasons Your Vision Is Blurry," 4 May 2018 Ultraviolet rays may play a role in the development of cataracts as well as growths on the surface of the eye called pterygiums, which can impede your vision. Amanda Gardner, Health.com, "Why Those Tiny Sunglasses Celebs Love Aren't Actually Good for Your Eyes," 13 June 2018

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.

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First Known Use of cataract

14th century, in the meaning defined at sense 1

History and Etymology for cataract

Latin cataracta waterfall, portcullis, from Greek kataraktēs, from katarassein to dash down, from kata- + arassein to strike, dash

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Last Updated

30 Aug 2018

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Time Traveler for cataract

The first known use of cataract was in the 14th century

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More Definitions for cataract

cataract

noun

English Language Learners Definition of cataract

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

: a large waterfall

cataract

noun
cat·a·ract | \ˈka-tə-ˌrakt \

Kids Definition of cataract

1 : a clouding of the lens of the eye or of the cover around the lens that blocks the passage of light

2 : a large waterfall

3 : a sudden rush or flow like a waterfall

cataract

noun
cat·a·ract | \ˈkat-ə-ˌrakt \

Medical Definition of cataract 

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

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Comments on cataract

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