[as-tuh-riz-uh m]
  1. Astronomy.
    1. a group of stars.
    2. a constellation.
  2. Mineralogy. 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 to draw attention to a passage it precedes.

Origin of asterism

1590–1600; < Greek asterism(ós) a marking with stars. See asterisk, -ism
Related formsas·ter·is·mal, adjective Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Examples from the Web for asterism

Historical Examples of asterism

British Dictionary definitions for asterism


  1. three asterisks arranged in a triangle (⁂ or ), to draw attention to the text that follows
  2. a starlike effect seen in some minerals and gemstones when viewed by reflected or transmitted light
  3. a cluster of stars, which may be a subset or a superset of a constellation

Word Origin for asterism

C16: from Greek asterismos arrangement of constellations, from astēr star
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for asterism

1590s, "a constellation, a group of stars," from Greek asterismos "a marking with stars," from aster "star" (see astro-). Any grouping of stars, whether a constellation or not (though in modern use, usually the latter). The "Big Dipper" is an asterism, not a constellation.

Online Etymology Dictionary, © 2010 Douglas Harper

asterism in Science


  1. A pattern of stars that is not one of the traditionally established, named constellations. Asterisms may constitute a part of a larger constellation, as in the case of the seven stars in Ursa Major that make up the Big Dipper, or they may be formed of individual stars in several different constellations, as in the case of the Summer Triangle, made up of Deneb (in Cygnus), Altair (in Aquila), and Vega (in Lyra).
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.