Columbia Encyclopedia

Search results

492 results found

geology

(Encyclopedia)geology, science of the earth's history, composition, and structure, and the associated processes. It draws upon chemistry, biology, physics, astronomy, and mathematics (notably statistics) for suppor...

molecule

(Encyclopedia)molecule mŏlˈəkyo͞ol [key] [New Lat.,=little mass], smallest particle of a compound that has all the chemical properties of that compound. A single atom is usually not referred to as a molecule, a...

air forces

(Encyclopedia)air forces, those portions of a nation's military organization employing heavier-than-air aircraft for reconnaissance, support of ground troops, aerial combat, and bombing of enemy lines of communicat...

radio astronomy

(Encyclopedia)radio astronomy, study of celestial bodies by means of the electromagnetic radio frequency waves they emit and absorb naturally. Radio waves also come from outside the Milky Way. These extragalact...

Pakistan

(Encyclopedia)CE5 Pakistan păkˈĭstănˌ, päkĭstänˈ [key], officially Islamic Republic of Pakistan, republic (2015 est. pop. 189,381,000), 310,403 sq mi (803,944 sq km), S Asia. Pakistan is bordered by Ind...

Iran

(Encyclopedia)CE5 Iran ēränˈ, ĭrănˈ [key], officially Islamic Republic of Iran, republic (2015 est. pop. 79,360,000), 636,290 sq mi (1,648,000 sq km), SW Asia. The country's name was changed from Persia to...

Denmark

(Encyclopedia)CE5 Denmark dĕnˈmärk [key], Dan. Danmark, officially Kingdom of Denmark, kingdom (2015 est. pop. 5,689,000), 16,629 sq mi (43,069 sq km), N Europe. It borders on Germany in the south, the North ...

isomer

(Encyclopedia)isomer īˈsəmər [key], in chemistry, one of two or more compounds having the same molecular formula but different structures (arrangements of atoms in the molecule). Isomerism is the occurrence of ...

Vienna, city and province, Austria

(Encyclopedia)Vienna vēĕnˈə [key], Ger. Wien, city and province (1991 pop. 1,539,848), 160 sq mi (414 sq km), capital and largest city of Austria and administrative seat of Lower Austria, NE Austria, on the Dan...

Russell, Bertrand Arthur William Russell, 3d Earl

(Encyclopedia)Russell, Bertrand Arthur William Russell, 3d Earl, 1872–1970, British philosopher, mathematician, and social reformer, b. Trelleck, Wales. As with his philosophical stance, Russell's positions on ...

Browse by Subject