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sextant

(Encyclopedia)CE5 Sextant sextant, instrument for measuring the altitude of the sun or another celestial body; such measurements can then be used to determine the observer's geographical position or for other n...

tarantula

(Encyclopedia)tarantula tərănˈchələ [key], name applied chiefly to species of the large, hairy spiders of the family Theraphosidae of North and South America, Africa, S and SE Asia, and Australia. The body of ...

polarography

(Encyclopedia)polarography pōˌlərŏgˈrəfē [key], in chemistry, method for analyzing the composition of a dilute electrolytic solution (see electrolyte). Two electrodes are placed in the solution: One has a fi...

handedness

(Encyclopedia)handedness, habitual or more skillful use of one hand as opposed to the other. Approximately 90% of humans are thought to be right-handed. It was traditionally argued that there is a slight tendency t...

hantavirus

(Encyclopedia)hantavirus, any of a genus (Hantavirus) of single-stranded RNA viruses that are carried by rodents and transmitted to humans when they inhale vapors from contaminated rodent urine, saliva, or feces. T...

medicinal plants

(Encyclopedia)medicinal plants, plants used as natural medicines. This practice has existed since prehistoric times. There are three ways in which plants have been found useful in medicine. First, they may be used ...

thermite

(Encyclopedia)thermite [from Thermit, a trade name], mixture of powdered or granular aluminum metal and powdered iron oxide. When ignited it gives off large amounts of heat. In wartime it has been used in incendiar...

sequence

(Encyclopedia)sequence, in mathematics, ordered set of mathematical quantities called terms. A sequence is said to be known if a formula can be given for any particular term using the preceding terms or using its p...

varicose vein

(Encyclopedia)varicose vein, superficial vessel that is abnormally lengthened, twisted, or dilated, seen most often on the legs and thighs. Varicose veins develop spontaneously, and are usually attributed to a here...

International Trade Commission, United States

(Encyclopedia)International Trade Commission, United States, independent agency of the U.S. government established in 1916 as the Tariff Commission; renamed International Trade Commission in 1975. It is charged wit...