Columbia Encyclopedia

Search results

500 results found

photon

(Encyclopedia)photon fōˈtŏn [key], the particle composing light and other forms of electromagnetic radiation, sometimes called light quantum. The photon has no charge and no mass. About the beginning of the 20th...

water beetle

(Encyclopedia)water beetle, name for aquatic beetles of several families. They should not be confused with water bugs, which are true bugs (order Hemiptera). The predaceous diving beetles (family Dytiscidae) are a ...

Cash, Johnny

(Encyclopedia)Cash, Johnny, 1932–2003, American singer and songwriter, b. Kingsland, Ark. Born to a farm family, he went to Memphis in 1955 and recorded such hits as “I Walk the Line” (1956) and “Ring of Fi...

black fly

(Encyclopedia)black fly, name for any of the flies of the family Simuliidae. The black fly is about 1⁄8 in. (3.2 mm) long and has large eyes, short legs, a stout, humped back, broad gauzy wings, and piercing-suck...

liquid

(Encyclopedia)liquid, one of the three commonly recognized states in which matter occurs, i.e., that state, as distinguished from solid and gas, in which a substance has a definite volume but no definite shape. T...

recycling

(Encyclopedia)recycling, the process of recovering and reusing waste products—from household use, manufacturing, agriculture, and business—and thereby reducing their burden on the environment. During World War ...

impressionism, in painting

(Encyclopedia)impressionism, in painting, late-19th-century French school that was generally characterized by the attempt to depict transitory visual impressions, often painted directly from nature, and by the use ...

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...

still life

(Encyclopedia)still life, a pictorial representation of inanimate objects. The term derives from the 17th-century Dutch still-leven, meaning a motionless natural object or objects. In East Asia still-life subj...

atom

(Encyclopedia)CE5 Bohr-Rutherford atom CE5 Probability distribution of the electron in the hydrogen atom: A. Ground state B. Highly excited state atom [Gr.,=uncuttable (indivisible)], basic unit of matte...