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1. Printing Three asterisks in a triangular formation used to call attention to a following passage.
2. Astronomy A pattern of stars that is not one of the traditionally established, named constellations, such as the Big Dipper or the Summer Triangle. Asterisms are often named and may be composed of stars that are members of one or more constellations.
3. Mineralogy A six-rayed starlike figure optically produced in some crystal structures by reflected or transmitted light.

[Greek asterismos, constellation, from astēr, star; see ster- in Indo-European roots.]

as′ter·is′mal adj.


1. (Printing, Lithography & Bookbinding) three asterisks arranged in a triangle (⁂ or the same symbol but upside down), to draw attention to the text that follows
2. (Geological Science) a starlike effect seen in some minerals and gemstones when viewed by reflected or transmitted light
3. (Astronomy) a cluster of stars, which may be a subset or a superset of a constellation
[C16: from Greek asterismos arrangement of constellations, from astēr star]


(ˈæs təˌrɪz əm)

a. a group of stars.
b. a constellation.
2. a property of some crystallized minerals of showing a starlike luminous figure in transmitted light or, in a cabochon-cut stone, by reflected light.
3. three asterisks (⁂ or ⁂) printed before a passage to draw attention to it.
[1590–1600; < Greek asterismós]


Rare. a constellation or small group of unrelated stars. — asterismal, adj.
See also: Astronomy
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.asterism - (mineralogy) a star-shaped figure with six rays that is seen in some crystal structures under reflected or transmitted lightasterism - (mineralogy) a star-shaped figure with six rays that is seen in some crystal structures under reflected or transmitted light
mineralogy - the branch of geology that studies minerals: their structure and properties and the ways of distinguishing them
star - a plane figure with 5 or more points; often used as an emblem
2.asterism - (astronomy) a cluster of stars (or a small constellation)asterism - (astronomy) a cluster of stars (or a small constellation)
natural object - an object occurring naturally; not made by man
astronomy, uranology - the branch of physics that studies celestial bodies and the universe as a whole
constellation - a configuration of stars as seen from the earth
References in periodicals archive ?
The Summer Triangle is an asterism - an easy-to-spot imaginary pattern of three bright stars which was first popularised in the 1950s by Sir Patrick Moore on his The Sky at Night programme.
Regulus, the brightest star of Leo the Lion, marks the tip of the prominent Sickle asterism.
One such asterism, was discovered by Dana Patchick in 1980 and named by his friend Steve Kufeld as Asterism Minor, but the correct indicated nr is Patchick 100.
A women's story from PI is that the old Saucepan (eight stars in Orion that make up the asterism called the Pot or Saucepan), when it gets full, will turn and tip.
However, locating M51 isn't difficult as it positioned towards the northeast border of Canes Venatici and only a few degrees from the handle of the seven stars that form the famous "Plough" or "Big Dipper" asterism of Ursa Major.
Confucius (Lunyu 2,1) equates the King with the -Northern Asterism," which "occupies its place, while all other stars revolve around it" (Pankenier 2004: 288).
Camelopardalis is the 18th largest constellation by area in the sky despite having no stars brighter than mag 4, although it does boast of the asterism Kemble's Cascade.
Among my favorites are three stars that make up the asterism (a group of stars that is not a constellation) called the "Summer Triangle.
Provisions are made for offerings on the asterism of Tiruvadirai, the natal star of Raja Raja I and on Revathi, the natal star of his (unnamed) queen.
Of all these gems, the most sought are "star" sapphires, that include an asterism, a phenomenon produced by a certain cut which causes the image of a star to appear in the gem.