Columbia Encyclopedia

Search results

500 results found

Engler, Adolf

(Encyclopedia)Engler, Adolf äˈdôlf ĕngˈlər [key], 1844–1930, German botanist. He emphasized the importance of geological history in the study of plant geography, and worked out an influential system of plan...

Gurugram

(Encyclopedia)Gurugram, formerly Gurgaon gûrˈgoun [key], city, Haryana state, N India, 15 mi (24 km) ...

joule

(Encyclopedia)joule jo͞ol, joul [key], abbr. J, unit of work or energy in the mks system of units, which is based on the metric system; it is the work done or energy expended by a force of 1 newton acting through ...

Pinyin

(Encyclopedia)Pinyin pĭnˈyĭnˈ [key] [Chin. Hanyu pinyin = Chinese phonetic alphabet], system of romanization of Chinese written characters, approved in 1958 by the government of the People's Republic of Chi...

Lorentz contraction

(Encyclopedia)Lorentz contraction lôrˈĕnts [key], in physics, contraction or foreshortening of a moving body in the direction of its motion, proposed by H. A. Lorentz on theoretical grounds and based on an earli...

momentum

(Encyclopedia)momentum mōmĕnˈtəm [key], in mechanics, the quantity of motion of a body, specifically the product of the mass of the body and its velocity. Momentum is a vector quantity; i.e., it has both a magn...

Murchison, Sir Roderick Impey

(Encyclopedia)Murchison, Sir Roderick Impey mûrˈkĭsən [key], 1792–1871, British geologist. He served in the Napoleonic Wars but after the peace turned his attention to science. In the 1830s he undertook the i...

barcode

(Encyclopedia)CE5 Barcode barcode, computer coding system that uses a printed pattern of lines and bars to identify such things as products, mail and packages, and customer accounts; the term also is used for s...