- (astronomy) A large planet composed mostly of gaseous hydrogen and helium, along with methane and ammonia; possibly with a solid core.
- 1954, Blish, James, “Solar Plexus”, in Beyond Human Ken, Random House, page 106:
- A quick glance over the boards revealed that there was a magnetic field of some strength near by, one that didn't belong to the invisible gas giant revolving half a million miles away.
- 2013 May-June, Kevin Heng, “Why Does Nature Form Exoplanets Easily?”, in American Scientist, volume 101, number 3, page 184:
- In the past two years, NASA’s Kepler Space Telescope has located nearly 3,000 exoplanet candidates ranging from sub-Earth-sized minions to gas giants that dwarf our own Jupiter.
large planet of gas
- “gas giant” in Jeff Prucher, editor, Brave New Words: The Oxford Dictionary of Science Fiction, Oxford; New York, N.Y.: Oxford University Press, 2007, →ISBN, pages 75–76.
- gas giant n. at the OED Science Fiction Citations Project