Columbia Encyclopedia

(Encyclopedia) cataract, in medicine, opacity of the lens of the eye, which impairs vision. In the young, cataracts are generally congenital or hereditary; later they are usually the result of degenerative changes b...

(Encyclopedia) hypertrophy hīpûrˈtrəfē [key], enlargement of a tissue or organ of the body resulting from an increase in the size of its cells. Such growth accompanies an increase in the functioning of the tiss...

(Encyclopedia) swim bladder, large, thin-walled sac in some fishes that may function in several ways, e.g., as a buoyant float, a sound producer and receptor, and a respiratory organ. The swim bladder, or air bladde...

(Encyclopedia) embolus ĕmˈbələs [key], foreign matter circulating in and obstructing a blood vessel. It may be a portion of a clot that has separated from the wall of a vessel (see thrombosis), a bubble of gas o...

(Encyclopedia) Sons of Liberty, secret organizations formed in the American colonies in protest against the Stamp Act (1765). They took their name from a phrase used by Isaac Barré in a speech against the Stamp Act...

(Encyclopedia) Elkins, Stephen Benton, 1841–1911, American statesman, b. Perry co., Ohio. He grew up in Missouri and after the outbreak of the Civil War enlisted in the Union army, although his father and brother ...

(Encyclopedia) Bhabha, Homi Jehangir jəhänˌgērˈ bäˈbä [key], 1909–66, Indian physicist, b. Bombay (now Mumbai). He was educated at the Royal Institute of Science, Bombay, and at Cambridge, England, where h...

(Encyclopedia) Raman, Sir Chandrasekhara Venkata chŭnˈdrəsĕkärə vĕngˈkətə räˈmən [key], 1888–1970, Indian physicist. He was professor of physics at Calcutta Univ. from 1917 to 1933. In Bangalore (now ...

(Encyclopedia) toxic waste is waste material, often in chemical form, that can cause death or injury to living creatures. It usually is the product of industry or commerce, but comes also from residential use, agric...

(Encyclopedia) McCumber, Porter James, 1858–1933, American political leader, b. Crete, Ill. He began law practice in North Dakota and served (1885–89) in the territorial legislature. From 1899 to 1923 he was a R...