dwarf planet

American  

[dwawrf plan-it] / ˈdwɔrf ˈplæn ɪt /

noun

Astronomy.

1. a spherical celestial body revolving about the sun, similar to a planet but not large enough to gravitationally clear its orbital region of most or all other celestial bodies. In 2006, the planet Pluto was reclassified as a dwarf planet.

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dwarf planet British  

noun

1. any celestial body within the solar system that is larger than a satellite but smaller than a planet, and that orbits the sun

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dwarf planet Scientific  

1. A celestial body that orbits the Sun and is massive enough to assume a nearly spherical shape, but that does not clear other bodies from the neighborhood around its orbit and is not a satellite of a planet. Dwarf planets include Ceres, Pluto, and Eris. This category was created by the International Astronomical Union in 2006.

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Etymology

Origin of dwarf planet

First recorded in 1990–95

Example Sentences

Since then, Pluto, our beloved ninth planet, has been demoted to a dwarf planet.

From Space Scoop • Oct. 15, 2025

Abrams picked up the torch for the seventh, eighth and ninth movies, he tasked their rebels with blowing up one the size of a dwarf planet.

From Salon • Jul. 19, 2024

After our moon and Pluto, the University of Bern team plans to explore similar scenarios for other outer Solar System bodies such as the Pluto-like dwarf planet Haumea.

From Science Daily • Apr. 15, 2024

But larger ones, roughly as massive as the asteroid Ceres or the dwarf planet Pluto, would get bigger on timescales of only a few hundred million years.

From Science Magazine • Dec. 13, 2023

Pluto got demoted from planet to dwarf planet, but we’d never treat each other as something lesser.

From "They Both Die at the End" by Adam Silvera