U·ra·nus (y-rānəs, yrə-nəs)
1. Greek Mythology The earliest supreme god, a personification of the sky, who was the son and consort of Gaea and the father of the Cyclopes and Titans.
2. The seventh planet from the sun, revolving about it every 84.01 years at a mean distance of approximately 2.9 billion kilometers (1.8 billion miles), having a mean equatorial diameter of 51,118 kilometers (31,763 miles) and a mass 14.6 times that of Earth.
[Late Latin Ūranus, from Greek ouranos, heaven, the god Uranus, Sense 2, from New Latin Ūranus, since Uranus was Saturn's father just as Saturn was Jupiter's father (thus making the order of the planets' names reflect mythological genealogy).]
(click for a larger image)Uranus
false-color image taken by the Hubble Space Telescope in 1998
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2019 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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