Columbia Encyclopedia

Search results

465 results found

credit card

(Encyclopedia)credit card, device used to obtain consumer credit at the time of purchasing an article or service. Credit cards may be issued by a business, such as a department store or an oil company, to make it e...

drone

(Encyclopedia)drone or remotely piloted vehicle, a pilotless craft guided by remote control. Aircraft, ships, and land vehicles can be designed or outfitted as drones. Underwater vessels—both piloted and pilotles...

sunspots

(Encyclopedia)sunspots, dark, usually irregularly shaped spots on the sun's surface that are actually solar magnetic storms. The spots are darker because the temperature of the spots is lower than that of the surro...

Pinter, Harold

(Encyclopedia)Pinter, Harold, 1930–2008, English dramatist. Born in Hackney in London's East End, the son of an English tailor of Eastern European Jewish ancestry, he studied at London's Royal Academy of Dramatic...

migration of animals

(Encyclopedia)migration of animals, movements of animals in large numbers from one place to another. In modern usage the term is usually restricted to regular, periodic movements of populations away from and back t...

astronomy

(Encyclopedia)astronomy, branch of science that studies the motions and natures of celestial bodies, such as planets, stars, and galaxies; more generally, the study of matter and energy in the universe at large. ...

Riga

(Encyclopedia)Riga rēˈgə [key], city (2011 provisional pop. 657,424), capital of Latvia, on the Daugava (Western Dvina) River near its entry into the Gulf of Riga. A major Baltic port, it is also a rail junction...

transistor

(Encyclopedia)CE5 Simple transistor circuit transistor, three-terminal, solid-state electronic device used for amplification and switching. It is the solid-state analog to the triode electron tube; the transist...

cosmology

(Encyclopedia)cosmology, area of science that aims at a comprehensive theory of the structure and evolution of the entire physical universe. The earliest pre-Ptolemaic theories assumed that the earth was the cent...

censorship

(Encyclopedia)censorship, official prohibition or restriction of any type of expression believed to threaten the political, social, or moral order. It may be imposed by governmental authority, local or national, by...