Definition of cataract
1 [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
2a obsolete : waterspoutb : waterfall; especially : a large one over a precipicec : steep rapids in a river the cataracts of the Niled : downpour, flood cataracts of rain cataracts of information
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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
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What a cataract of disaster has poured out upon us since then.
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A cataract is a clouding of the lens inside the eye.
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Luckily, the area is riddled with more accessible and exclusive cataracts, especially on the property of Hidden Valley Inn (tel.
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The eye's lubricating fluid contains mucus protein, which over time can build up and cloud your vision like a snot cataract.
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.
Origin and Etymology of cataract
Latin cataracta waterfall, portcullis, from Greek kataraktēs, from katarassein to dash down, from kata- + arassein to strike, dash
First Known Use: 14th century
Other Geology Terms
anthracite, boulder, cwm, erratic, igneous, intrusive, mesa, sedimentary, silt, swale
CATARACT Defined for English Language Learners
cataract
playDefinition of cataract for English Language Learners
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medical : a condition in which a part of your eye (called the lens) becomes cloudy and you cannot see well
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: a large waterfall
CATARACT Defined for Kids
cataract
playDefinition of cataract for Students
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
Medical Dictionary
cataract
playMedical Definition of cataract
: a clouding of the lens of the eye or its surrounding transparent membrane that obstructs the passage of light
Learn More about cataract
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See words that rhyme with cataract Thesaurus: All synonyms and antonyms for cataract Spanish Central: Translation of cataract Nglish: Translation of cataract for Spanish speakers Britannica English: Translation of cataract for Arabic speakers Britannica.com: Encyclopedia article about cataract
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