Definition of "aster" []

• Any of various plants of the genus Aster in the composite family, having radiate flower heads with white, pink, or violet rays and a usually yellow disk. (noun)
• The China aster. (noun)
• Biology A star-shaped structure formed in the cytoplasm of a cell and having raylike fibers that surround the centrosome during mitosis. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "After breakfast in Britain, I came out in the dawn and picked a purple aster from a flower bed."
• "+ The word aster may mean a comet; the star of the Magi was a comet."
• "The name aster is derived from the Latin word astrum and the Greek word astron, both of which mean star."