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tornado

(Encyclopedia)tornado, dark, funnel-shaped cloud containing violently rotating air that develops below a heavy cumulonimbus cloud mass and extends toward the earth. The funnel twists about, rises and falls, and whe...

genetic testing

(Encyclopedia)genetic testing, medical screening for genetic disorders, by examining either a person's DNA directly or a person's biochemistry or chromosomes for indirect evidence. Testing may be done to identify a...

gorilla

(Encyclopedia)gorilla, an ape, genus Gorilla, native to the lowland and mountain forests of western and central equatorial Africa. The two gorilla species are the western, comprising the western lowland (G. gorilla...

electronic game

(Encyclopedia)electronic game, device or computer program that provides entertainment by challenging a person's eye-hand coordination or mental abilities. Made possible by the development of the microprocessor, ele...

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...

molecular weight

(Encyclopedia)molecular weight, weight of a molecule of a substance expressed in atomic mass units (amu). The molecular weight may be calculated from the molecular formula of the substance; it is the sum of the ato...

coral

(Encyclopedia)coral, small, sedentary marine animal, related to the sea anemone but characterized by a skeleton of horny or calcareous material. The skeleton itself is also called coral. Although most corals form c...

clam

(Encyclopedia)clam, common name for certain bivalve mollusks, especially for marine species that live buried in mud or sand and have valves (the two pieces of the shell) of equal size. The oval valves, which cover ...

plague

(Encyclopedia)plague, any contagious, malignant, epidemic disease, in particular the bubonic plague and the black plague (or Black Death), both forms of the same infection. These acute febrile diseases are caused b...

Norton Sound

(Encyclopedia)Norton Sound, inlet of the Bering Sea, c.150 mi (240 km) long and 125 mi (200 km) across at its widest point, W Alaska, S of the Seward Peninsula. Norton Bay is its northeast arm. Nome is on the north...