Columbia Encyclopedia

(Encyclopedia) appendix, small, worm-shaped blind tube, about 3 in. (7.6 cm) long and 1⁄4 in. to 1 in. (.64–2.54 cm) thick, projecting from the cecum (part of the large intestine) on the right side of the lower ...

(Encyclopedia) hammerhead shark, active, surface-living shark, genus Sphyrina. Its curious head has lateral projections resembling the crossbar of a T, and its eyes and ears are located in the outer tips of the proj...

(Encyclopedia) head-hunting, practice of taking and preserving the head of a slain enemy. It has occurred throughout the world from ancient times into the 20th cent. In Europe, it flourished in the Balkans until the...

(Encyclopedia) primary, in the United States, a preliminary election in which the candidate of a party is nominated directly by the voters. The establishment of the primary system resulted from the demand to elimina...

(Encyclopedia) vendetta vĕndĕtˈə [key] [Ital.,=vengeance], feud between members of two kinship groups to avenge a wrong done to a relative. Although the term originated in Corsica, the custom has also been pract...

(Encyclopedia) relapsing fever, infectious disease caused by a spirochete bacteria of the genus Borrelia and characterized by a high fever that breaks and then recurs a one to two weeks later. Relapsing fever may be...

(Encyclopedia) shale, sedimentary rock formed by the consolidation of mud or clay, having the property of splitting into thin layers parallel to its bedding planes. Shale tends to be fissile, i.e., it tends to split...

(Encyclopedia) endometriosis ĕnˌdəmēˌtrē-ōˈsĭs [key], a condition in which small pieces of the endometrium (the lining of the uterus) migrate to other places in the pelvic area. The endometrial fragments ma...

(Encyclopedia) gonorrhea gŏnərēˈə [key], common infectious disease caused by a bacterium (Neisseria gonorrhoeae), involving chiefly the mucous membranes of the genitourinary tract. It may occasionally spread to...

(Encyclopedia) euchre yo͞oˈkər [key], card game, played usually by four persons (two sets of partners). The game originated among the Amish and was a popular card game in America in the late 19th cent. The pack h...