What does aster mean?
An aster is a flowering plant belonging to the daisy family, prized for its star-shaped blooms that carry a yellow centre surrounded by slender rays of purple, blue, pink, or white. Asters are among the most recognisable flowers of late summer and autumn, when they provide a vital late-season source of nectar for butterflies and other pollinators. Many species are native to North America and Eurasia, and popular cultivated kinds include the New England aster and the China aster, widely grown in borders and cottage gardens. The name derives from the Greek word for 'star', a reference to the radiating form of the flower head. Beyond botany, the term also appears in cell biology, where an 'aster' describes the star-shaped array of microtubules surrounding a centrosome during cell division. Whether admired in a garden or observed under a microscope, the aster consistently evokes its stellar namesake.
A plant of the daisy family (genus Aster or closely related genera), bearing daisy-like flowers with a yellow central disc and coloured ray florets, typically blooming in late summer or autumn.
"She planted asters along the border to ensure colour right up until the first frost."
Botanical reclassification has moved many former Aster species into other genera (e.g. Symphyotrichum), though they are still commonly called asters in gardening contexts.
In cell biology, a star-shaped cluster of microtubules radiating from a centrosome during mitosis.
"Each spindle pole was anchored by a prominent aster visible under fluorescence microscopy."
Regular plural: simply add -s. Used both for individual plants and collectively for beds or displays of them.
"The meadow was dotted with asters and goldenrod in equal measure."
The aster is named for looking like a tiny star — and when a fungus blighted it, botanists renamed half the genus, but 'aster' still means 'star' in Greek.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of aster
The word 'aster' comes from Latin aster, itself borrowed from Greek ἀστήρ (astēr), meaning 'star'. It entered English in the early 17th century, first applied to the star-shaped flowers of the genus Aster. The same Greek root gives English a whole family of star-related words, including asteroid, asterisk, astral, and disaster (originally 'an unfavourable star').
How aster is actually used
In everyday use, 'aster' almost always refers to the flowering plant, especially as a garden or wildflower staple of autumn. In cell biology, 'aster' has a precise technical meaning referring to the star-shaped microtubule array at spindle poles during mitosis — context usually makes the intended sense clear. Botanical classification of what counts as a 'true' aster has been revised in recent decades, so some plants formerly called asters now sit in other genera.
Easily confused with aster
An asterisk is the typographic star symbol (*), while an aster is an actual star-shaped flower.
Daisies belong to related genera (e.g. Bellis) and are distinct from true asters in the genus Aster, though both have daisy-like flower heads.