the large and varied plant family Compositae (or Asteraceae), typified by herbaceous plants having alternate, opposite, or whorled leaves and a whorl of bracts surrounding the flower heads, which are usually composed of a disk containing tiny petalless flowers and a ray of petals extending from the flowers at the rim of the disk, some flower heads being composed only of a disk or a ray and some plants having clusters of flower heads, and including the aster, daisy, dandelion, goldenrod, marigold, ragweed, sunflower, thistle, and zinnia.
Words nearby composite family
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
Science definitions for composite family
A very large family of flowering plants, Compositae (or Asteraceae), comprising about 1,100 genera and more than 20,000 species, including the daisy, lettuce, and marigold. The composite plants are eudicots and are considered to be the most highly evolved plants. Their inflorescences are characterized by many small flowers arranged in a head that resembles a single flower and arises from an involucre of bracts. A head may consist of both ray flowers and disk flowers, as in the sunflower, of disk flowers only, as in the burdock, or of ray flowers only, as in the dandelion.
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