Saturn

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun Roman Mythology The god of agriculture.
• noun The sixth planet from the sun and the second largest in the solar system, having a sidereal period of revolution about the sun of 29.5 years at a mean distance of about 1.43 billion kilometers (891 million miles), a mean diameter of approximately 121,000 kilometers (75,000 miles), and a mass 96 times that of Earth.

from The Century Dictionary.

• noun An ancient Italic deity, popularly believed to have appeared in Italy in the reign of Janus, and to have instructed the people in agriculture, gardening, etc., thus elevating them from barbarism to social order and civilization.
• noun The most remote of the anciently known planets, appearing at brightest like a first-magnitude star.
• noun In alchemy and old chemistry, lead.
• noun In heraldry, a tincture, the color black, when blazoning is done by means of the heavenly bodies. See blazon, n., 2.
• noun The thickness of the ring is considerably less than a hundred miles. Its plane is inclined 7° to the planet's equator and 28° 10’ to the earth's orbit. When Saturn appears in the hind legs of Leo or the water of Aquarius, we see the rings edgewise, and they pass out of sight, remaining invisible as long as the sun shines upon the side away from us, for the ring only shows by the reflected light of the sun. They are best seen when the planet is in Taurus and Scorpio. As soon as Saturn was examined with a telescope (by Galileo), it was seen to present an extraordinary appearance; but this was first recognized and proved to be a ring by Huygens in 1659. In 1674 J. D. Cassini saw the separation between rings A and B, which is hence called the Cassinian division. (It has also been erroneously called Ball's division.) The dusky ring was discovered in 1850 at Cambridge, Massachusetts, by G. P. Bond. The ring was first assumed to be solid. Laplace showed that, upon that assumption, it must be upheld by the attractions of the satellites. B. Peirce in 1851 demonstrated the ring to be fluid—that is, to consist of vast numbers of particles, or small bodies, free to move relatively to one another. This had been suggested by Roberval in the seventeenth century. See cut on preceding page.

from the GNU version of the Collaborative International Dictionary of English.

• noun (Roman Myth.) One of the elder and principal deities, the son of Cœlus and Terra (Heaven and Earth), and the father of Jupiter. The corresponding Greek divinity was Kro`nos, later CHro`nos, Time.
• noun (Astron.) One of the planets of the solar system, next in magnitude to Jupiter, but more remote from the sun. Its diameter is seventy thousand miles, its mean distance from the sun nearly eight hundred and eighty millions of miles, and its year, or periodical revolution round the sun, nearly twenty-nine years and a half. It is surrounded by a remarkable system of rings, and has eight satellites.
• noun (Alchem.), Archaic The metal lead.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• proper noun Roman mythology The god of fertility and agriculture, equivalent to the Greek Kronos.
• proper noun astronomy, astrology The second largest planet in Earth's solar system, famous for its large rings and until recent times the furthest known; represented in astronomy and astrology by ♄.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun (Roman mythology) god of agriculture and vegetation; counterpart of Greek Cronus
• noun a giant planet that is surrounded by three planar concentric rings of ice particles; the 6th planet from the sun