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Tagus

(Encyclopedia)Tagus tāˈgəs [key], Span. Tajo, Port. Tejo, river, c.585 mi (940 km) long, rising in the mountains E of Madrid, E Spain, and draining the central part of the Iberian Peninsula. The Tagus flows nort...

thresher shark

(Encyclopedia)thresher shark, long-tailed, warm-water shark, genus Alopias. The upper fork of its tail is slender and sickle-shaped and is about equal in length to the rest of the body. This shark uses its tail str...

sodium hydroxide

(Encyclopedia)sodium hydroxide, chemical compound, NaOH, a white crystalline substance that readily absorbs carbon dioxide and moisture from the air. It is very soluble in water, alcohol, and glycerin. It is a caus...

sodium silicate

(Encyclopedia)sodium silicate, any one of several compounds containing sodium oxide, Na2O, and silica, Si2O, or a mixture of sodium silicates. Sodium orthosilicate is Na4SiO4 (or 2Na2O·SiO2); sodium metasilicate i...

speedometer

(Encyclopedia)speedometer, instrument that indicates speed. A cable from an automotive speedometer is attached to the rear of the transmission of an automobile; the cable turns at a rate proportional to the speed o...

rudder

(Encyclopedia)rudder, mechanism for steering an airplane or a ship. In ships it is a flat-surfaced structure hinged to the stern and controlled by a helm. When the ship is on a straight course, the rudder is in lin...

pipit

(Encyclopedia)pipit, common name for a group of chiefly Eurasian and African birds that together with the wagtails constitute a subfamily of songbirds related to the Old World warblers and thrushes. Pipits are trim...

fish, in zoology

(Encyclopedia)CE5 Anatomy of a ray-finned fish fish, limbless aquatic vertebrate animal with fins and internal gills. Traditionally the living fish have been divided into three class: the primitive jawless fish...

ecology

(Encyclopedia)ecology, study of the relationships of organisms to their physical environment and to one another. The study of an individual organism or a single species is termed autecology; the study of groups of ...

Colorado River storage project

(Encyclopedia)Colorado River storage project, a multipurpose plan, undertaken by the U.S. Bureau of Reclamation in 1956, to control the flow of the upper Colorado and its tributaries and to aid in the development o...

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