Pluto

noun

Plu·​to ˈplü-(ˌ)tō 

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

Free streaming service Pluto TV is set as the exclusive media partner, hosting the on-demand release. —Emily Longeretta, Variety, 28 Aug. 2025

First discovered: 12:53 p.m. Aug. 28 Initial location: Placer County, Calif. Fire type: Wildfire Fire name: Pluto A new wildfire was reported today at 12:53 p.m. in Placer County, California. —Ca Wildfire Bot, Sacbee.com, 28 Aug. 2025

Venus confronting Pluto may try to talk you out of going bigger than ever before. —Usa Today, USA Today, 27 Aug. 2025

Still, the influence of Pluto retrograde is dragging you back to tend to your daily rituals and work routines, which is frustrating. —Valerie Mesa, People.com, 27 Aug. 2025

Word History

Etymology

Latin Pluton-, Pluto, from Greek Ploutōn

First Known Use

14th century, in the meaning defined at sense 1

Rhymes for Pluto

• basuto
• prosciutto

Kids Definition

Pluto

noun

Plu·​to ˈplüt-ō 

: a large object in the outermost part of the solar system that is often considered one of the planets see note at planet