Definition from Wiktionary, the free dictionary
asterism (plural asterisms)
- (astronomy) A small group of stars that forms a visible pattern but is not an official constellation.
- The Big Dipper, Summer Triangle, and Orion's Belt are asterisms.
- A rarely used typographical symbol (⁂, three asterisks arranged in a triangle), used to call attention to a passage or to separate subchapters in a book.
- (mineralogy) A star-shaped figure exhibited by some crystals by reflected light (as in a star sapphire) or by transmitted light (as in some mica).
small group of stars
a star-shaped figure exhibited by some crystals