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 for cataract

Synonyms

cascade, fall(s), waterfall

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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

Shannon says the vision loss in her right eye is the result of childhood cataracts that were never properly treated, and her left was damaged by retinal detachment, a disorder of the eye in which the retina separates from the layer underneath. Emily Strohm, PEOPLE.com, "Mama June Says She Gained 25 Lbs. Because She Is Going Blind and Can't Exercise," 13 June 2018 Her older sister, Lyna Yip, who arrived in the United States with two of her uncles ahead of her parents, sister and brother, also had surgery to remove cataracts but emerged with better vision. Richard Sandomir, New York Times, "Julie Yip-Williams, Writer of Candid Blog on Cancer, Dies at 42," 22 Mar. 2018 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

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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Statistics for cataract

Last Updated

8 Nov 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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