as·​ter | \ ˈa-stər How to pronounce aster (audio) \

Definition of aster

 (Entry 1 of 2)

1 [New Latin, from Latin, aster, from Greek aster-, astēr star, aster — more at star]
a : any of various chiefly fall-blooming leafy-stemmed composite herbs (Aster and closely related genera) with often showy heads containing disk flowers or both disk and ray flowers
2 [New Latin, from Greek aster-, astēr] : a system of microtubules arranged radially about a centriole at either end of the mitotic or meiotic spindle

Definition of -aster (Entry 2 of 2)

: one that is inferior or not genuine criticaster

Illustration of aster

Illustration of aster


aster 1a

In the meaning defined above

Examples of aster in a Sentence

Recent Examples on the Web: Noun Then mix in plants that will extend the flower show through summer into fall, when late-season perennials such as aster, black-eyed Susan, and Russian sage take over. Megan Hughes, Better Homes & Gardens, "7 of the Most Common Perennial Garden Mistakes to Avoid," 18 June 2020 For the late fall also grow some duranta, mint marigold, Mexican flame vine, and fall aster. Calvin Finch,, "Calvin Finch: How to attract butterflies to your San Antonio garden all year long," 21 May 2020 The Stokes aster is one of my favorite summer perennials and grows happily in hot, humid conditions. Adrian Higgins, Washington Post, "It’s time to plan the new season’s garden, and it pays to be picky," 11 Mar. 2020 Sow warm-weather plants like nightshades and cucurbits indoors for transplanting in May. Transplant aster, viola, zinnia, marigold, and delphinium from cold frames to beds. Heather Arndt Anderson, Sunset Magazine, "Your Ultimate Spring Gardening To-Do List for March and April," 16 Mar. 2020 When cells rest between divisions, microtubule asters organize the cell’s contents. Quanta Magazine, "Unscrambled Eggs: Self-Organization Restores Cells’ Order," 2 Jan. 2020 Adding clumps of pollen-rich blooms (think daisy-like coneflowers, sunflowers, asters) to a vegetable mix enhances pollination and boosts harvests. Washington Post, "Advice to first-time gardeners: Think small. Find your spot.," 24 Dec. 2019 Deer will eat fall aster, so the planting site must be selected to avoid their browsing. Calvin Finch,, "What’s blooming now in our chilly San Antonio gardens," 14 Nov. 2019 Mönch’ aster, catmint, lavender, rudbeckia, and Salvia chamaedryoides. Thad Orr, Sunset, "Your Essential Gardening To-Do List for April," 22 Jan. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'aster.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of aster


1664, in the meaning defined at sense 1a

History and Etymology for aster

Noun suffix

Middle English, from Latin, suffix denoting partial resemblance

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Time Traveler for aster

Time Traveler

The first known use of aster was in 1664

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Statistics for aster

Last Updated

28 Jun 2020

Cite this Entry

“Aster.” Dictionary, Merriam-Webster, Accessed 12 Aug. 2020.

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More Definitions for aster


How to pronounce -aster (audio)

English Language Learners Definition of aster

: a type of plant that is grown in gardens for its colorful flowers


as·​ter | \ ˈa-stər How to pronounce aster (audio) \

Kids Definition of aster

: any of various herbs related to the daisies that have leafy stems and white, pink, purple, or yellow flower heads which bloom in the fall


as·​ter | \ ˈas-tər How to pronounce aster (audio) \

Medical Definition of aster

: a system of microtubules arranged in rays around a centriole at either end of the mitotic or meiotic spindle The first stage in the formation of the mitotic spindle in a typical animal cell is the appearance of microtubules in a "sunburst" arrangement, or aster, around each centrosome during early prophase. — Gerald Karp, Cell and Molecular Biology: Concepts and Experiments, 6th edition, 2010

called also cytaster

More from Merriam-Webster on aster

Spanish Central: Translation of aster

Nglish: Translation of aster for Spanish Speakers

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