galaxy

noun

gal·​axy ˈga-lək-sē 

plural galaxies

1

a

often Galaxy : 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

a

: an assemblage of brilliant or notable persons or things

a galaxy of artists

b

: world sense 11

… remained galaxies apart on the issue …

—Newsweek

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.

Synonyms of galaxy

• world

Examples of galaxy in a Sentence

The event was attended by a galaxy of artists.

they're a galaxy apart when it comes to politics

Recent Examples on the Web

Radio galaxies are useful in this way because radio waves have long enough wavelengths to slip through cosmic gas and dust rather than being absorbed, as happens with other forms of electromagnetic radiation. —Robert Lea, Space.com, 14 Nov. 2025

The galaxy becomes accessible with this interactive play space. —Lindsay Kimble, PEOPLE, 14 Nov. 2025

These are distant galaxies that emit particularly strong radio waves. —Chris Young, Interesting Engineering, 14 Nov. 2025

In the new story, Mario, Luigi and Princess Peach will venture into the galaxy, traveling to different lands from the beloved video game. —Mckinley Franklin, HollywoodReporter, 12 Nov. 2025

Word History

Etymology

Middle English galaxias, galaxie, borrowed from Late Latin galaxias, borrowed from Greek galaxías (probably originally conjoined with kýklos "wheel"), from galakt-, stem of gála "milk" (going back to Indo-European *glkt-, attested elsewhere only in Latin lact-, lac "milk," Armenian kat'n) + -ias, noun suffix, especially of natural phenomena

First Known Use

15th century, in the meaning defined at sense 1a

Phrases Containing galaxy

• elliptical galaxy
• Milky Way galaxy
• radio galaxy
• satellite galaxy
• Seyfert galaxy
• spiral galaxy

Kids Definition

galaxy

noun

gal·​axy ˈgal-ək-sē 

plural galaxies

1

: milky way galaxy

2

: one of the very large groups of stars and other matter that are found throughout the universe

Etymology

Middle English galaxie "the Milky Way," from Latin galaxias (same meaning), from Greek galaxias "Milky Way," from galakt-, gala "milk"