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-3 in the Appendix of Indo-European roots.]
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