cataract

noun

cat·​a·​ract ˈka-tə-ˌrakt How to pronounce cataract (audio)
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 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.

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
These examples are automatically compiled from online sources to illustrate current usage. Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.
One mother carries forward her young son, who is blinded by easily treatable cataracts. Charlie Campbell / Jakarta, TIME, 14 Oct. 2024 Many of his videos can be classified as philanthropic, including one in which Donaldson paid for 1,000 cataract surgeries. Max Hauptman, USA TODAY, 19 Sep. 2024 The research found an appendectomy in the same hospital can cost as much as 32 times on the upper end what that facility’s lowest cost is for the service; cataract surgery can cost nine times and cesareans eight times the lowest cost at the same facility. Gretchen Morgenson, NBC News, 14 Sep. 2024 May reduce the need for glasses and contact lenses; some people may not need these visual aids at all Lasers also are used in other types of surgery, including those to treat cataracts. Vanessa Caceres, Verywell Health, 11 Sep. 2024 See all Example Sentences for cataract 

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

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

Podcast

Dictionary Entries Near cataract

Cite this Entry

“Cataract.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/cataract. Accessed 16 Nov. 2024.

Kids Definition

cataract

noun
cat·​a·​ract ˈkat-ə-ˌrakt How to pronounce cataract (audio)
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 How to pronounce cataract (audio)
: a clouding of the lens of the eye or its surrounding transparent membrane that obstructs the passage of light

More from Merriam-Webster on cataract

Last Updated: - Updated example sentences
Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!