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noun Plu·to \ˈplü-(ˌ)tō\

: the object in our solar system that in the past was thought to be the planet farthest from the sun but that is no longer considered to be a planet

Full Definition of PLUTO

:  the Greek god of the underworld — compare dis
[New Latin] :  a dwarf planet occupying an orbit that crosses the orbit of Neptune

Usage Discussion of PLUTO

In 2006 the International Astronomical Union defined planet in such a way as to exclude Pluto, reclassifying it instead as a dwarf planet. Although discussion of the matter continues, the change has been widely accepted.

Origin of PLUTO

Latin Pluton-, Pluto, from Greek Ploutōn
First Known Use: 14th century

Rhymes with PLUTO

PLUTO Defined for Kids


noun Plu·to \ˈplü-tō\

Definition of PLUTO for Kids

:  a celestial object that orbits the sun at an average distance of 3.7 million miles (5.9 million kilometers) and has a diameter of about 1500 miles (2300 kilometers) and is often considered one of the planets


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