The Collaborative International Dictionary of English v.0.48:

Erigeron \Erigeron\ n.
   a cosmopolitan genus of usually perennial herbs with
   asterlike flowers; the leaves were formerly used medicinally,
   but now are only occasionally so used.

   Syn: genus Erigeron.
        [WordNet 1.5]

WordNet (r) 3.0 (2006):

Erigeron
    n 1: cosmopolitan genus of usually perennial herbs with flowers
         that resemble asters; leaves occasionally (especially
         formerly) used medicinally [syn: Erigeron, genus
         Erigeron]