Columbia Encyclopedia

Search results

102 results found

energy, sources of

(Encyclopedia)energy, sources of, origins of the power used for transportation, for heat and light in dwelling and working areas, and for the manufacture of goods of all kinds, among other applications. The develop...

drill, tool

(Encyclopedia)drill, tool used to create a hole, usually in some hard substance, by its rotary or hammering action. Many different tools make up the drill family. The awl is a pointed instrument used for piercing s...

nuclear weapons

(Encyclopedia)nuclear weapons, weapons of mass destruction powered by atomic, rather than chemical, processes. Nuclear weapons produce large explosions and hazardous radioactive byproducts by means of either nuclea...

plating

(Encyclopedia)plating, application of a plate, or coat, of metal to a surface for decoration, reflection of light, protection against corrosion, or increased wearing quality. The practice is of ancient origin: gild...

Phaeophyta

(Encyclopedia)Phaeophyta fēŏfˈətə [key], phylum (division) of the kingdom Protista consisting of those organisms commonly called brown algae. Many of the world's familiar seaweeds are members of Phaeophyta. Th...

Normandy campaign

(Encyclopedia)Normandy campaign, June to Aug., 1944, in World War II. The Allied invasion of the European continent through Normandy began about 12:15 a.m. on June 6, 1944 (D-day). The plan, known as Operation Over...

pipe

(Encyclopedia)pipe, hollow structure, usually cylindrical, for conducting materials. It is used primarily to convey liquids, gases, or solids suspended in a liquid, e.g., a slurry. It is also used as a conduit for ...

reproduction

(Encyclopedia)CE5 Examples of asexual reproduction reproduction, capacity of all living systems to give rise to new systems similar to themselves. The term reproduction may refer to this power of self-duplicati...

Carolingian architecture and art

(Encyclopedia)Carolingian architecture and art, art forms and structures created by the Carolingians. Toward the beginning of the Carolingian Period, in the 8th cent., a gradual change appeared in Western culture a...

protozoan

(Encyclopedia)protozoan prōˌtəzōˈən [key], informal term for the unicellular heterotrophs of the kingdom Protista. Protozoans comprise a large, diverse assortment of microscopic or near-microscopic organisms ...