Columbia Encyclopedia

(Encyclopedia) rift valley, elongated depression, trough, or graben in the earth's crust, bounded on both sides by normal faults and occurring on the continents or under the oceans. The central flat block forming th...

(Encyclopedia) Kahoolawe kähōˈōläˈvā, –wā, kähōˈläˈ– [key], uninhabited island, 45 sq mi (117 sq km), central Hawaii; separated from Maui island to the NE by Alalakeiki Channel. The low island, dott...

(Encyclopedia) bearing, machine part designed to reduce friction between moving parts or to support moving loads. There are two main kinds of bearings: the antifriction type, such as the roller bearing and the ball ...

(Encyclopedia) tamoxifen təmŏkˈsĭfĕnˌ [key], synthetic hormone used in the treatment of breast cancer. Introduced in 1978, tamoxifen is used to prevent recurrences of cancer in women who have already undergone...

(Encyclopedia) Chatham Islands, island group, 385 sq mi (996 sq km), South Pacific, c.500 mi (800 km) E of New Zealand, to which it belongs. The two largest islands are Chatham Island, which has a large central lago...

(Encyclopedia) arrhythmia ārĭᵺˈmēə [key], disturbance in the rate or rhythm of the heartbeat. Various arrhythmias can be symptoms of serious heart disorders; however, they are usually of no medical significan...

(Encyclopedia) Schiavo case, the legal battles over the guardianship and rights of Theresa Maria Schindler Schiavo (1963–2005). Terri Schiavo was incapacitated and hospitalized in 1990, after she collapsed when he...

(Encyclopedia) Youth, Isle of, Span. Isla de la Juventud, island and special municipality (1989 est. pop. 71,500), 1,180 sq mi (3,056 sq km), off SW Cuba, from which it is separated by the Batabanó Gulf. Until 1978...

(Encyclopedia) Hokkaido hōkīˈdō [key], island, c.30,130 sq mi (78,040 sq km), N Japan, separated from Ho...

(Encyclopedia) Barentsøya bârˈənts, bärˈ– [key], island of Svalbard, 513 sq mi (1,329 sq km), in Barents Sea between Spitsbergen and Edgeøya. The island rises to 1,302 ft (397 m). ...