asterism

noun

as·​ter·​ism ˈa-stə-ˌri-zəm 

1

a

: a group of stars that form a pattern in the night sky

On October evenings, when the trees have shed their leaves and stars become visible through the twigs, our best-known asterism, the Big Dipper, passes under the north pole.

—George Lovi

Note: The term asterism does not now usually refer to a constellation but to a star pattern that makes up part of a constellation or that includes stars from more than one constellation.

b

: a small group of stars

2

: a star-shaped figure exhibited by some crystals by reflected light (as in a star sapphire) or by transmitted light (as in some mica)

Examples of asterism in a Sentence

Recent Examples on the Web

The Dipper is not a constellation in of itself, but an asterism, a prominent pattern or group of stars, typically having a popular name, belonging to a specific constellation. —Joe Rao, Space.com, 9 June 2025

Leading the way is the Summer Triangle asterism, made up of the bright stars Vega, Deneb and Altair. —Mike Lynch, Twin Cities, 1 June 2025

The current North Star can be found easily by locating the Big Dipper asterism in Ursa Minor, which is high overhead this time of year. —Anthony Wood, Space.com, 20 May 2025

Also within the constellation Sagittarius is the teapot asterism, a small pattern of stars that gives the Milky Way a distinct semblance of rising steam. —Jack Knudson, Discover Magazine, 19 May 2025

Word History

Etymology

borrowed from Greek asterísmos, from asterízein "to arrange in constellations" (from aster-, astḗr "star" + -izein -ize) + -ismos -ism — more at star entry 1

First Known Use

1598, in the meaning defined at sense 1a

Rhymes for asterism

• autism
• fascism
• racism
• sikhism
• statism
• sufism
• thomism
• tourism
• tropism
• abolitionism
• aldosteronism
• americanism