Columbia Encyclopedia

Search results

438 results found

Presbyterianism

(Encyclopedia)Presbyterianism, form of Christian church organization based on administration by a hierarchy of courts composed of clerical and lay presbyters. Holding a position between episcopacy (government by bi...

carbon

(Encyclopedia)CE5 The three solid forms of pure carbon: In the diamond crystal each carbon atom is surrounded symmetrically by four other carbons (at each of the four corners of a tetrahedron). In the graphite c...

space probe

(Encyclopedia)space probe, space vehicle carrying sophisticated instrumentation but no crew, designed to explore various aspects of the solar system (see space exploration). Unlike an artificial satellite, which is...

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...

battery, electric

(Encyclopedia)CE5 Lead storage cell: At the lead-dioxide electrode, electrons from the circuit combine with lead dioxide and sulfuric acid to form lead sulfate and water. At the spongy-lead electrode, lead react...

iron

(Encyclopedia)iron, metallic chemical element; symbol Fe [Lat. ferrum]; at. no. 26; at. wt. 55.845; m.p. about 1,535℃; b.p. about 2,750℃; sp. gr. 7.87 at 20℃; valence +2, +3, +4, or +6. Iron is biologically s...

trigonometry

(Encyclopedia)trigonometry [Gr.,=measurement of triangles], a specialized area of geometry concerned with the properties of and relations among the parts of a triangle. Spherical trigonometry is concerned with the ...

Utah , state, United States

(Encyclopedia)CE5 Utah yo͞oˈtäˌ [key], Rocky Mt. state of the W United States. It is bordered by Idaho and Wyoming (N), Colorado (E), Arizona (S), and Nevada (W), and touches New Mexico in the SE, at the Fou...

nucleic acid

(Encyclopedia)CE5 Replication of strands of DNA CE5 nucleic acid, any of a group of organic substances found in the chromosomes of living cells and viruses that play a central role in the storage and replica...

vector

(Encyclopedia)vector, quantity having both magnitude and direction; it may be represented by a directed line segment. Many physical quantities are vectors, e.g., force, velocity, and momentum. Thus, in specifying a...