Cat"a*ract (?), n. [L. cataracta, catarracles, a waterfall, Gr. , , fr. to break down; in the passive, to fall or rush down (of tumors) to burst; down + to break.]
A great fall of water over a precipice; a large waterfall.
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.
A kind of hydraulic brake for regulating the action of pumping engines and other machines; -- sometimes called dashpot.
© Webster 1913.