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noun gal·axy \ˈga-lək-sē\

Simple Definition of galaxy

  • astronomy : any one of the very large groups of stars that make up the universe

  • the Galaxy : the galaxy in which we live

  • : a large group of important or well-known people or things

Source: Merriam-Webster's Learner's Dictionary

Full Definition of galaxy



  1. 1 a often capitalized :  milky way galaxy —used with the b :  any of the very large groups of stars and associated matter that are found throughout the universe

  2. 2 a :  an assemblage of brilliant or notable persons or things <a galaxy of artists> b :  world 11 <remained galaxies apart on the issue — Newsweek>

Examples of galaxy in a sentence

  1. The event was attended by a galaxy of artists.

  2. <they're a galaxy apart when it comes to politics>

Did You Know?

The system of stars that includes our sun looks, in the night sky, like a broad band of light. We call this band the Milky Way. The idea of the whiteness of the Milky Way being similar to that of milk is much older than the English language, however. Galaxias, the Greek word for the Milky Way, was derived from the Greek gala, “milk.” English galaxy, derived from Greek galaxias, was not used until the 19th century as a generic term for other star systems as well as the one in which we live.

Origin and Etymology of galaxy

Middle English galaxie, galaxias, from Late Latin galaxias, from Greek, from galakt-, gala milk; akin to Latin lac milk

First Known Use: 14th century

GALAXY Defined for Kids


noun gal·axy \ˈga-lək-sē\

Definition of galaxy for Students



  1. 1 :  milky way galaxy

  2. 2 :  one of the very large groups of stars, gas, and dust that make up the universe

History for galaxy

The band of light that crosses a clear night sky is caused by many faint stars. We call this band the Milky Way because it looks a bit like a stream of milk. The stars of the Milky Way belong to our galaxy, the Milky Way galaxy. The idea that the Milky Way looks like milk is much older than the English language, however. The ancient Greek name for this star system, galaxias, was formed from the Greek word gala, “milk.” The English word galaxy was borrowed from the Greek name.

Seen and Heard

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to make consistent or congruous

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