Columbia Encyclopedia

Search results

279 results found

sleep apnea

(Encyclopedia)sleep apnea, episodes of interrupted breathing during sleep. Obstructive sleep apnea is a common disorder in which relaxation of muscles in the throat repeatedly close off the airway during sleep; the...

Ripon, Frederick John Robinson, 1st earl of

(Encyclopedia)Ripon, Frederick John Robinson, 1st earl of rĭpˈən [key], 1782–1859, British statesman, better known as Viscount Goderich. Entering Parliament as a Tory in 1806, he sponsored the unpopular corn l...

alpaca

(Encyclopedia)alpaca ălpăkˈə [key], partially domesticated South American mammal, Lama pacos, of the camel family. Genetic studies show that it is a descendant of the vicuña. Although the flesh is sometimes us...

indulgence

(Encyclopedia)indulgence, in the Roman Catholic Church, the pardon of temporal punishment due for sin. It is to be distinguished from absolution and the forgiveness of guilt. The church grants indulgences out of th...

meditation

(Encyclopedia)meditation, religious discipline in which the mind is focused on a single point of reference. It may be a means of invoking divine grace, as in the contemplation by Christian mystics of a spiritual th...

Boutwell, George Sewall

(Encyclopedia)Boutwell, George Sewall so͞oˈəl boutˈwəl, –wĕl [key], 1818–1905, American politician, b. Brookline, Mass. He served seven terms in the Massachusetts legislature between 1842 and 1851, was el...

Snowden, Philip Snowden, 1st Viscount

(Encyclopedia)Snowden, Philip Snowden, 1st Viscount snōˈdən [key], 1864–1937, British statesman. Born to poverty, he was a civil service clerk until crippled by a spinal ailment. Resigning in 1893, he began to...

aldehyde

(Encyclopedia)CE5 Aldehydes aldehyde ălˈdəhīd [key] [alcohol + New Lat. dehydrogenatus=dehydrogenated], any of a class of organic compounds that contain the carbonyl group, >C=-->O, and in which t...

nitric acid

(Encyclopedia)nitric acid, chemical compound, HNO3, colorless, highly corrosive, poisonous liquid that gives off choking red or yellow fumes in moist air. It is miscible with water in all proportions. It forms an a...

ruthenium

(Encyclopedia)ruthenium ro͞othēˈnēəm [key], metallic chemical element; symbol Ru; at. no. 44; at. wt. 101.07; m.p. about 2,310℃; b.p. about 3,900℃; sp. gr. 12.41 at 20℃; valence commonly +2, +3, +4, +6, ...