aster

1 of 2

noun

as·​ter ˈa-stər 

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

b

: china aster

2

: a system of microtubules arranged radially about a centriole at either end of the mitotic or meiotic spindle

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

Noun

In late spring and early summer, the meadows are awash with vibrant wildflowers like lupine, Indian paintbrush, and asters. —AFAR Media, 7 July 2025

Combined with hostas in a shade bed, white wood aster will cover dry areas filled with shade tree roots. —Judy Nauseef, Better Homes & Gardens, 24 June 2025

To attract butterflies, consider planting milkweed, verbena and aster. —Clarence Schmidt, San Diego Union-Tribune, 16 Apr. 2025

Cosmos are members of the aster family (Asteracea), whose members produce disk-like flowers packed with tiny blooms and surrounded by showy ray petals. —Kim Toscano, Southern Living, 15 Apr. 2025

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

Phrases Containing aster

• aster yellows
• China aster

Rhymes for aster

• aster
• blaster
• caster
• castor
• faster
• gaster
• laster
• bandmaster
• broadcaster
• cadastre
• disaster
• forecaster

Kids Definition

aster

noun

as·​ter ˈas-tər 

: 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 

: 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