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


noun suffix

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 Late season: bottle gentian, Gentiana andrewsii; showy goldenrod, Solidago speciosa (superfood); New England aster, Aster novae-angliae (superfood); white turtlehead, Chelone glabra (immune builder). Jennifer Rude Klett, Milwaukee Journal Sentinel, 13 Apr. 2022 Plants in the aster, mint, carrot, and milkweed families are among the most visited if your space is limited. Miri Talabac, Baltimore Sun, 6 Apr. 2022 King Richard co-star Saniyya Sidney wore an aster-blue off-the-shoulder gown by Zuhair Murad. Laurie Brookins, The Hollywood Reporter, 27 Feb. 2022 Like its Eastern cousin, this western native aster blooms from late summer into fall. Thad Orr, Better Homes & Gardens, 3 Nov. 2021 The sturdier parts of a plant, such as the woody trunk and branches of a tree, the roots of an aster or coneflower, or the underground bulbs of tulips, wait out the winter. Beth Botts,, 19 Dec. 2021 Cynara scolymus is a perennial thistle in the aster family. Janet Carson, Arkansas Online, 13 Dec. 2021 Mint marigold starts blooming a little later in the season than fall aster. Calvin Finch, San Antonio Express-News, 12 Nov. 2021 This compact variety of native New England aster begins blooming in late summer and keeps going until frost. Thad Orr, Better Homes & Gardens, 3 Nov. 2021 See More

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.

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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Last Updated

18 Apr 2022

Cite this Entry

“Aster.” Dictionary, Merriam-Webster, Accessed 27 May. 2022.

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More Definitions for aster


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

Kids Definition of aster

: any of various herbs related to the daisy 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

called also cytaster

More from Merriam-Webster on aster

Nglish: Translation of aster for Spanish Speakers


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