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; kata` down + &?; to break.]
1. A
great fall of water over
a precipice; a large waterfall.
2.
(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.
3. (Mach.)
A kind of
hydraulic brake for regulating the action of pumping engines and other machines; -- sometimes
called dashpot.
Hear it pronounced