aster

1 of 2

noun

as·​ter ˈa-stər How to pronounce aster (audio)
1
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
: a system of microtubules arranged radially about a centriole at either end of the mitotic or meiotic spindle

Illustration of aster

Illustration of aster
  • aster 1a

-aster

2 of 2

noun suffix

: one that is inferior or not genuine
criticaster

Examples of aster in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Noun
Like most members of the aster family, golden ragwort is deer- and rabbit-resistant. Samantha Johnson, Martha Stewart, 5 Mar. 2026 Most garden center asters have summer or fall blooms and prefer full sun and moist soil, with some protection from mid-day sun appreciated in the lower South. Michelle Darrisaw, Southern Living, 1 Mar. 2026 Pass Mountain Trail seems to be the star this year with a range of blooms that include poppies, lupines, brittles, fiddleneck, cinchweed, chuparosa and asters. Roger Naylor, AZCentral.com, 21 Feb. 2026 The over 100 native aster species in North America come in a kaleidoscope of colors and can tolerate a variety of conditions. Anne Readel, Better Homes & Gardens, 20 Feb. 2026 See All Example Sentences for aster

Word History

Etymology

Noun

(sense 1) borrowed from New Latin, genus name, going back to Latin aster-, astēr "a plant, probably Aster amellus," borrowed from Greek aster-, astḗr "star, the plant Aster amellus"; (sense 2) borrowed from Greek aster-, astḗr "star" — more at star entry 1

Noun suffix

Middle English, from Latin, suffix denoting partial resemblance

First Known Use

Noun

1664, in the meaning defined at sense 1a

Time Traveler
The first known use of aster was in 1664

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Cite this Entry

“Aster.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/aster. Accessed 9 Mar. 2026.

Kids Definition

aster

noun
as·​ter ˈas-tər How to pronounce aster (audio)
: any of various mostly fall-blooming leafy-stemmed herbs related to the daisies usually with showy white, pink, purple, or yellow flower heads

Medical Definition

aster

noun
as·​ter ˈas-tər How to pronounce aster (audio)
: 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

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