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Ebola virus

(Encyclopedia)Ebola virus ēbōˈlə [key], a virus of the genus Ebolavirus, which belongs to a family (Filoviridae) of RNA viruses that cause hemorrhagic fevers. The viruses, named for a river in Congo (Kinshasa) ...

endocytosis

(Encyclopedia)endocytosis ĕnˌdōsītōˈsəs [key], in biology, process by which substances are taken into the cell. When the cell membrane comes into contact with a suitable food, a portion of the cell cytoplasm...

Norman Conquest

(Encyclopedia)Norman Conquest, period in English history following the defeat (1066) of King Harold of England by William, duke of Normandy, who became William I of England. The conquest was formerly thought to hav...

Neolithic period

(Encyclopedia)Neolithic period or New Stone Age. The term neolithic is used, especially in archaeology and anthropology, to designate a stage of cultural evolution or technological development characterized by the ...

strontium

(Encyclopedia)strontium strŏnˈshēəm [key] [from Strontian, a Scottish town], a metallic chemical element; symbol Sr; at. no. 38; at. wt. 87.62; m.p. 769℃; b.p. 1,384℃; sp. gr. 2.6 at 20℃; valence +2. Stro...

light

(Encyclopedia)light, visible electromagnetic radiation. Of the entire electromagnetic spectrum, the human eye is sensitive to only a tiny part, the part that is called light. The wavelengths of visible light range ...

Moorish art and architecture

(Encyclopedia)Moorish art and architecture, branch of Islamic art and architecture developed in the westernmost lands of the Muslims, known as the Maghreb: N Africa and Spain. The Great Mosque at Al Qayrawan in Tun...

More, Sir Thomas

(Encyclopedia)More, Sir Thomas (Saint Thomas More), 1478–1535, English statesman and author of Utopia, celebrated as a martyr in the Roman Catholic Church. He received a Latin education in the household of Cardin...

mercury poisoning

(Encyclopedia)mercury poisoning, tissue damage resulting from exposure to more than trace amounts of the element mercury or its compounds. Elemental mercury (the silver liquid familiar from thermometers) is the mos...

loom

(Encyclopedia)loom, frame or machine used for weaving; there is evidence that the loom has been in use since 4400 b.c. Modern looms are of two types, those with a shuttle (the part that carries the weft through the...