cataract

noun

cat·​a·​ract ˈka-tə-ˌrakt 

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

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

cataractous

ˌka-tə-ˈrak-təs 

adjective

Did you know?

Cataract dates to the 14th century and comes from the Latin word cataracta, meaning "portcullis." The Latin pertains to the ocular cataract, probably because it obstructs one's vision much like the portcullis's heavy iron grating obstructs passage into a fortress or castle. Cataracta has another meaning, however—"waterfall"—and that meaning gave English 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.

Synonyms

• cascade
• fall(s)
• 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

Similarly, cataract surgery has been shown to increase economically valuable activities by 40% to 50%. —Gabrielle Emanuel, NPR, 3 Apr. 2024

By age 80, over half of all Americans have cataracts. —Discover Magazine, 27 Mar. 2024

Eye conditions that can cause night blindness include: glaucoma, a disease that damages the eye’s optic nerves and blood vessels cataracts, cloudy areas in the lens that distort or block the passage of light through the lens dry eye syndrome. —Matthew Solan, Chicago Tribune, 31 Jan. 2024

While in Rowland Heights, cataracts robbed her of her ability to see. —Molly Castle Work | Kff Health News, Los Angeles Times, 22 Jan. 2024

The leading cause of blindness was cataracts, a condition that is routinely cured through surgery in America. —Jan Goldsmith, San Diego Union-Tribune, 22 Mar. 2024

Drucker cites the success of Alcon Laboratories co-founder Bill Conner, who recognized that eye surgeons had come to dread cutting a ligament during the systemized process of cataract operations. —Kate Vitasek, Forbes, 29 Nov. 2023

Today, Kilimanjaro Centre reaches 14 African countries where medical facility partners annually perform thousands of cataract surgeries. —Jan Goldsmith, San Diego Union-Tribune, 22 Mar. 2024

Meanwhile the animals, some of whom were once deployed in America’s foreign wars, are helping break new ground with research on kidney stones, cataracts, weight issues and all the other indignities faced by aging veterans everywhere. —Andrew Van Dam, Washington Post, 15 Mar. 2024

Word History

Etymology

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

First Known Use

14th century, in the meaning defined at sense 1

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Kids Definition

cataract

noun

cat·​a·​ract ˈkat-ə-ˌrakt 

1

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

2

a

: a large waterfall

b

: a sudden rush like a waterfall : flood

Medical Definition

cataract

noun

cat·​a·​ract ˈkat-ə-ˌrakt 

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