Columbia Encyclopedia

Search results

224 results found

rock

(Encyclopedia)rock, aggregation of solid matter composed of one or more of the minerals forming the earth's crust. The scientific study of rocks is called petrology. Rocks are commonly divided, according to their o...

Alexander the Great

(Encyclopedia)CE5 Empire of Alexander the Great (including dependencies) Alexander the Great or Alexander III, 356–323 b.c., king of Macedon, conqueror of much of Asia. Whether or not Alexander had plans fo...

cocaine

(Encyclopedia)cocaine kōkānˈ, kōˈkān [key], alkaloid drug derived from the leaves of the coca shrub. A commonly abused illegal drug, cocaine has limited medical uses, most often in surgical applications that ...

laser

(Encyclopedia)CE5 Ordinary light sources produce incoherent light, while a laser produces a beam of coherent light. laser [acronym for light amplification by stimulated emission of radiation], device for the cr...

bee

(Encyclopedia)bee, name for flying insects of the superfamily Apoidea, in the same order as the ants and the wasps. Bees are characterized by their enlarged hind feet, typically equipped with pollen baskets of stif...

topology

(Encyclopedia)CE5 Möbius strip: On the ordinary flat loop (A), an ant walking along the middle of the strip will pass only around the outside of the strip. If the strip is cut along the dotted line, twisted onc...

book

(Encyclopedia)book. The word book has come to have many meanings, e.g., any collection of sheets of paper, wood, or other material sewn or bound together; a division of a written work (books of the Bible, books of ...

rice

(Encyclopedia)rice, cereal grain (Oryza sativa) of the grass family (Graminae), probably native to the deltas of the great Asian rivers—the Ganges, the Chang (Yangtze), and the Tigris and Euphrates. The plant is ...

Gaza Strip

(Encyclopedia)Gaza Strip gäzˈə [key], rectangular coastal area, c.140 sq mi (370 sq km), SW Asia, on the ...

global warming

(Encyclopedia)global warming, the gradual increase of the temperature of the earth's lower atmosphere as a result of the increase in greenhouse gases since the Industrial Revolution. Global warming and its effects,...