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ether, in chemistry

(Encyclopedia)CE5 Ethers ether, any of a number of organic compounds whose molecules contain two hydrocarbon groups joined by single bonds to an oxygen atom. The most common of these compounds is ethyl ether, C...

harrow, in agriculture

(Encyclopedia)harrow, farm implement, consisting of a wooden or metal framework bearing metal disks, teeth, or sharp projecting points, called tines, which is dragged over plowed land to pulverize the clods of eart...

mass, in physics

(Encyclopedia)mass, in physics, the quantity of matter in a body regardless of its volume or of any forces acting on it. The term should not be confused with weight, which is the measure of the force of gravity (se...

lens, in optics

(Encyclopedia)CE5 Lenses lens, device for forming an image of an object by the refraction of light. In its simplest form it is a disk of transparent substance, commonly glass, with its two surfaces curved or wi...

medusa, in zoology

(Encyclopedia)medusa, in zoology, scientific name for the jellyfish, i.e., the free-swimming stage of various animals in the phylum Cnidaria. See polyp and medusa. ...

abacus, in mathematics

(Encyclopedia)CE5 Chinese abacus: Numbers are represented by moving beads to the central crossbar. abacus ăbˈəkəs, əbăkˈ– [key], in mathematics, simple device for performing arithmetic calculations. Th...

style, in literature

(Encyclopedia)style, in literature, the mysterious yet recognizable result of a successful blending of form with content. Generally speaking, all the arts reflect one of two stylistic tendencies: the classical or t...

Saturn, in astronomy

(Encyclopedia)CE5 Saturn and its ring system as seen from Earth Saturn, in astronomy, 6th planet from the sun. Saturn has 82 confirmed natural satellites, many of which have not been named. Five of the discov...

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,...

Phoebe, in astronomy

(Encyclopedia)Phoebe fēˈbē [key], in astronomy, one of the named moons, or natural satellites, of Saturn. Also known as Saturn IX (or S9), Phoebe is 137 mi (220 km) in diameter, orbits Saturn at a mean distance ...