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Janus, in astronomy

(Encyclopedia)Janus jāˈnəs [key], in astronomy, one of the named moons, or natural satellites, of Saturn. Also known as Saturn X (or S10), Janus is an irregularly shaped (nonspherical) body measuring about 122 m...

Aquila, in astronomy

(Encyclopedia)Aquila [Lat.,=the eagle], equatorial constellation located N of Sagittarius and Capricornus, lying partly in the Milky Way. It is sometimes depicted as an eagle. It contains the bright star Altair (Al...

joint, in anatomy

(Encyclopedia)joint, in anatomy, juncture between two bones. Some joints are immovable, e.g., those that connect the bones of the skull, which are separated merely by short, tough fibers of cartilage. Movable joint...

joint, in geology

(Encyclopedia)joint, in geology, fracture in rocks along which no appreciable movement has occurred (see fault). Nearly vertical, or sheet, joints that result from shrinkage during cooling are commonly found in ign...

pyramid, in geometry

(Encyclopedia) CE5 Pyramid pyramid, in geometry, solid figure bounded by a polygon (the base, or directrix) and the surface generated by a moving line (the generator) passing through a fixed point (vertex) and c...

quadrant, in technology

(Encyclopedia)quadrant, in technology, angle-measuring device based on a scale of 90°. It is sometimes confused with the sextant, a similar instrument based on a scale of 60°. The quadrant is rarely used today. ...

Queenborough-in-Sheppey

(Encyclopedia)Queenborough-in-Sheppey, town (1991 pop. 33,362), on the Isle of Sheppey, Kent, SE England, at the confluence of the Medway and Thames rivers. Radios, furniture, glass, rubber products, and clothing a...

radical, in chemistry

(Encyclopedia)radical, in chemistry, group of atoms that are joined together in some particular spatial structure and that take part in most chemical reactions as a single unit. Important inorganic radicals include...

radical, in mathematics

(Encyclopedia)radical, in mathematics, symbol () placed over a number or expression, called the radicand, to indicate a root of the radicand. When used without a sign or index number, as in 4, it designates the pos...

rocket, in botany

(Encyclopedia)rocket, in botany, popular name for several plants of the family Cruciferae (or Brassicaceae; mustard family). The dame's, or damask, violet, damewort, or sweet rocket is Hesperis matronalis, a hardy,...
 

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