Pluto

noun

Plu·​to ˈplü-(ˌ)tō How to pronounce Pluto (audio)
1
: the Greek god of the underworld compare dis
2
[New Latin] : a dwarf planet occupying an orbit that crosses the orbit of Neptune
Is Pluto a planet?: Usage Guide

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.

Examples of Pluto in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Volume and channel rockers can be found below, along with menu and dedicated service buttons for Amazon Prime Video, Apple TV, Netflix, Pluto TV, TCL TV, and YouTube. PCMAG, 19 Feb. 2025 This is followed by Mercury’s debut in Aries (your communication sector), where the messenger planet will make a sextile to Pluto in your sign on March 5. Valerie Mesa, People.com, 18 Feb. 2025 But Charon was half the size of Pluto itself, so big that the Pluto-Charon combination are sometimes referred to as a double planet, according to NASA. Elizabeth Weise, USA TODAY, 18 Feb. 2025 Lonely Pluto would eventually turn out to be not so lonely after all. Jeffrey Kluger, TIME, 18 Feb. 2025 See all Example Sentences for Pluto 

Word History

Etymology

Latin Pluton-, Pluto, from Greek Ploutōn

First Known Use

14th century, in the meaning defined at sense 1

Time Traveler
The first known use of Pluto was in the 14th century

Dictionary Entries Near Pluto

Cite this Entry

“Pluto.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/Pluto. Accessed 22 Feb. 2025.

Kids Definition

Pluto

noun
Plu·​to ˈplüt-ō How to pronounce Pluto (audio)
: a large object in the outermost part of the solar system that is often considered one of the planets see note at planet

More from Merriam-Webster on Pluto

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