1. A large or high waterfall.
2. A great downpour; a deluge.
3. Medicine Opacity of the lens or capsule of the eye, causing impairment of vision or blindness.
[Middle English cataracte, from Old French, from Latin cataracta, from Greek katarraktēs, kataraktēs, downrush, waterfall, portcullis, probably from katarassein, to dash down (kat-, kata-, cata- + arassein, to strike). Sense 3, from a comparison to a portcullis or other falling impediment or covering.]
cat′a·ractous (-răktəs) adj.
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2022 by HarperCollins Publishers. All rights reserved.
Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
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