from The American Heritage® Dictionary of the English Language, 5th Edition.

  • noun A large or high waterfall.
  • noun A great downpour; a deluge.
  • noun Medicine Opacity of the lens or capsule of the eye, causing impairment of vision or blindness.

from The Century Dictionary.

  • To form cataracts.
  • To pour, like a cataract.
  • noun A descent of water over a steeply sloping but not perpendicular surface, as the cataracts of the Nile and the Orinoco; hence, especially in poetical use, any large waterfall, as that of the Niagara.
  • noun Any furious rush or downpour of water.
  • noun A disease of the eye, characterized by opacity of the lens.
  • noun In fortification, a herse.
  • noun A regulator for single-acting steam-engines, invented by Smeaton.
  • noun The plungeon, a kind of cormorant: so called because of its violent downward flight in seizing its prey.
  • noun In mech., a device for regulating the number of strokes per minute in a Cornish pumping-engine, in which the velocity of a falling weight, or a spring-weighted piston, is governed by the flow of water through a variable opening, whose cross-section can be controlled at will, so that the period of the stroke or the interval between strokes can be made longer or shorter.

from the GNU version of the Collaborative International Dictionary of English.

  • noun A great fall of water over a precipice; a large waterfall.
  • noun (Surg.) An opacity of the crystalline lens, or of its capsule, which prevents the passage of the rays of light and impairs or destroys the sight.
  • noun (Mach.) A kind of hydraulic brake for regulating the action of pumping engines and other machines; -- sometimes called dashpot.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

  • noun obsolete A waterspout
  • noun A large waterfall; steep rapids in a river.
  • noun A flood of water
  • noun An overwhelming downpour or rush
  • noun pathology A disease of the eye causing its opacity and, unless treated, leading to blindness.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

  • noun a large waterfall; violent rush of water over a precipice
  • noun an eye disease that involves the clouding or opacification of the natural lens of the eye


from The American Heritage® Dictionary of the English Language, 4th Edition

[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.]

from Wiktionary, Creative Commons Attribution/Share-Alike License

From Latin cataracta 'waterfall, portcullis', from Ancient Greek καταράκτης, from καταράσσω (katarassō, "I pour down").


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  • "It is true that in this time 1870 people set their faces hard for photographs, partly from custom, partly because of deficits in photographic technology, but this crowd might not have smiled for the better part of a century. The women seem suspended in a state somewhere between melancholy and fury and are surrounded by old men in strange beards that look as if someone had dabbed glue at random points on their faces, then hurled buckets of white hair in their direction. The day on which this photograph was taken must have been breezy because the longest and strangest beard, stuck on the oldest living citizen, Allen Tibbits, is a white blur resembling a cataract."

    —Erik Larson, Thunderstruck (New York: Crown Publishers, 2006), 31

    July 7, 2009

  • Away, ye gay landscapes, ye garden of roses!

    In you let the minions of luxury rove;

    Restore me to the rocks, where the snowflake reposes,

    Though still they are sacred to freedom and love:

    Yet, Caledonia, beloved are thy mountains,

    Round their white summits though elements war;

    Though cataracts foam 'stead of smooth-flowing fountains,

    I sigh for the valley of dark Loch na Garr.

    - Lord Byron, 'Lachin Y Gair', 1807.

    September 30, 2009

  • "n. In fortification, a herse.

    n. A regulator for single-acting steam-engines, invented by Smeaton.

    n. The plungeon, a kind of cormorant: so called because of its violent downward flight in seizing its prey."

    -- CD&C

    March 18, 2013