The Collaborative International Dictionary of English v.0.48:

Compositae \Com*pos"i*t[ae]\, n. pl. [NL., from L. compositus
   made up of parts. See Composite.] (Bot.)
   A large family of dicotyledonous plants, having their flowers
   arranged in dense heads of many small florets and their
   anthers united in a tube. The daisy, dandelion, and asters,
   are examples.
   [1913 Webster]

WordNet (r) 3.0 (2006):

Compositae
    n 1: plants with heads composed of many florets: aster; daisy;
         dandelion; goldenrod; marigold; lettuces; ragweed;
         sunflower; thistle; zinnia [syn: Compositae, family
         Compositae, Asteraceae, family Asteraceae, aster
         family]