[ joo-pi-ter ]

  1. Also called Jove. the supreme deity of the ancient Romans: the god of the heavens and of weather.: Compare Zeus.

  2. Astronomy. the planet fifth in order from the sun, having an equatorial diameter of 88,729 miles (142,796 km), a mean distance from the sun of 483.6 million miles (778.3 million km), a period of revolution of 11.86 years, and at least 14 moons. It is the largest planet in the solar system.

  1. Military. a medium-range U.S. ballistic missile of the 1950s, powered by a single liquid-fueled rocket engine.

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British Dictionary definitions for Jupiter (1 of 2)


/ (ˈdʒuːpɪtə) /

  1. (in Roman tradition) the king and ruler of the Olympian gods: Greek counterpart: Zeus

British Dictionary definitions for Jupiter (2 of 2)


/ (ˈdʒuːpɪtə) /

  1. the largest of the planets and the fifth from the sun. It has 67 satellites and is surrounded by a transient planar ring system consisting of dust particles. Mean distance from sun: 778 million km; period of revolution around sun: 11.86 years; period of axial rotation: 9.83 hours; diameter and mass: 11.2 and 317.9 times that of earth respectively: See Galilean satellite

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Scientific definitions for Jupiter


[ jōōpĭ-tər ]

  1. The fifth planet from the Sun and the largest, with a diameter about 11 times that of Earth. Jupiter is a gas giant made up mostly of hydrogen and helium. It turns on its axis faster than any other planet in the solar system, taking less than ten hours to complete one rotation; this rapid rotation draws its atmospheric clouds into distinct belts parallel to its equator. Jupiter has more known moons by far than any other planet in the solar system-as many as 63, with new ones being discovered regularly in recent years-and it has a faint ring system that was unknown until 1979, when the Voyager space probe investigated the planet. A persistent anticyclonic storm known as the Great Red Spot is Jupiter's most prominent feature. See Table at solar system.

The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

Cultural definitions for Jupiter (1 of 2)


The Roman name of Zeus, the most powerful of the gods of classical mythology.

Notes for Jupiter

The fifth and largest planet from the sun (the Earth is third) is named Jupiter.

In astronomy, the largest planet in the solar system; the fifth major planet from the sun. Jupiter is largely composed of gases. It is named after the ruler of the Roman gods (see under “Mythology and Folklore”). Jupiter is visible from Earth.

The New Dictionary of Cultural Literacy, Third Edition Copyright © 2005 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.