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water pollution

(Encyclopedia)water pollution, contamination of water resources by harmful wastes; see also sewerage, water supply, pollution, and environmentalism. The United States has enacted extensive federal legislation to ...

plant

(Encyclopedia)plant, any organism of the plant kingdom, as opposed to one of the animal kingdom or of the kingdoms Fungi, Protista, or Monera in the five-kingdom system of classification. (A more recent system, sug...

rocket, in aeronautics

(Encyclopedia)CE5 Relative positions of the components of the Saturn V rocket, the U.S. space vehicle used in the moon missions rocket, any vehicle propelled by ejection of the gases produced by combustion of s...

rubber

(Encyclopedia)CE5 Basic molecules in rubber rubber, any solid substance that upon vulcanization becomes elastic; the term includes natural rubber (caoutchouc) and synthetic rubber. The term elastomer is sometim...

surgery

(Encyclopedia)surgery, branch of medicine concerned with the diagnosis and treatment of injuries and the excision and repair of pathological conditions by means of operative procedures (see also anesthesia; medicin...

Chordata

(Encyclopedia)CE5 Common features in representative groups of the phylum Chordata Chordata kôrdāˈtə, –däˈ– [key], phylum of animals having a notochord, or dorsal stiffening rod, as the chief internal ...

nucleus, in physics

(Encyclopedia)nucleus, in physics, the extremely dense central core of an atom. Following the discovery of radioactivity by A. H. Becquerel in 1896, Ernest Rutherford identified two types of radiation given off b...

Mollusca

(Encyclopedia)Mollusca məlŭsˈkə [key], taxonomic name for the one of the largest phyla of invertebrate animals (Arthropoda is the largest) comprising more than 50,000 living mollusk species and about 35,000 fos...

Elements (table)

(Encyclopedia)Elements 1 Parentheses indicate most stable isotope; brackets enclose lower and upper bounds of weight variation. ...

science

(Encyclopedia)science [Lat. scientia=knowledge]. For many the term science refers to the organized body of knowledge concerning the physical world, both animate and inanimate, but a proper definition would also hav...