The Collaborative International Dictionary of English v.0.48:

Grindelia \Grin*de"li*a\, n. [NL. Named after D. H. Grindel, a
   Russian.] (Med.)
   The dried stems and leaves of tarweed (Grindelia), used as
   a remedy in asthma and bronchitis.
   [1913 Webster]

WordNet (r) 3.0 (2006):

Grindelia
    n 1: large genus of coarse gummy herbs of western North and
         Central America [syn: Grindelia, genus Grindelia]