Definition: Common name of several different genera and species in the flowering plants family Asteraceae.
Description: The family Asteraceae or, alternatively, family Compositae, known as the aster, daisy or sunflower family , is a taxon of dicotyledonous flowering plants. The family name is derived from the genus Aster and refers to the star-shaped flower head of its members, typified well by the daisy. The Asteraceae is the second largest family in the Division Magnoliophyta, with some 1,100 genera and over 20,000 recognized species. Only the orchid family (Orchidaceae) is larger, with about 25,000 described species.
Plants in the family Asteraceae typically have one or both of two kinds of florets. The outer perimeter of a flower head like that of a sunflower is composed of florets possessing a long strap-like petal, termed a ligule; these are the ray florets. The inner portion of the flower head (or disc) is composed of small flowers with tubular corollas; these are the disc florets. The composition of asteraceous inflorescences varies from all ray flowers (like dandelions, genus Taraxacum) to all disc flowers (like pineapple weeds).
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