gas giant

American  

[gas jahy-uhnt] / ˈgæs ˌdʒaɪ ənt /

noun

Astronomy.

1. a giant planet composed mostly of hydrogen and helium: the two gas giants in our solar system, Jupiter and Saturn, are sometimes called failed stars because their composition is similar to that of stars, but this is largely considered misleading, as gas giants, unlike brown dwarfs, do not form as stars do.

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gas giant British  

noun

1. one of the four planets in our solar system that are composed chiefly of hydrogen and helium, namely Jupiter, Saturn, Uranus, and Neptune

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gas giant Scientific  

1. A large, massive, low-density planet composed primarily of hydrogen, helium, methane, and ammonia in either gaseous or liquid state. Gas giants have swirling atmospheres primarily of hydrogen and helium, with no well-defined planetary surface; they are assumed to have rocky cores. They are also characterized by ring systems, although only Saturn's is readily visible from Earth. Our solar system contains four gas giants: Jupiter, Saturn, Uranus, and Neptune. The majority of extrasolar planets discovered so far are the size of the solar system's gas giants, although they orbit their stars much more closely and may differ in composition from ours.

2. Also called Jovian planet

3. Compare terrestrial planet

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Etymology

Origin of gas giant

First recorded in 1950–55

Example Sentences

BP said it was halting stock buybacks as the oil and gas giant said it wanted to rebuild its balance sheet.

From MarketWatch

BP said it was halting stock buybacks as the oil and gas giant said it wanted to rebuild its balance sheet.

From MarketWatch

The researchers estimate that the gas giant contains roughly one and a half times more oxygen than the sun.

From Science Daily

The gas giant WASP-121b is surrounded by not one, but two enormous streams of helium that stretch across more than half of its orbit.

From Science Daily

ExxonMobil and Chevron, two oil and gas giants also based in Texas, have likewise declined to publicly share any plans to extract Venezuelan oil, or lack thereof.

From Salon