Wordnet 3.0
NOUN (1)
1. 
 genus of North American and Asiatic perennial herbs having pinnatisect leaves small heads of drooping yellowish to purple flowers; 
 sometimes includes species often placed in genus Nabalus; 
[syn: Prenanthes, genus Prenanthes]
WordNet (r) 3.0 (2006):
genus Prenanthes
    n 1: genus of North American and Asiatic perennial herbs having
         pinnatisect leaves small heads of drooping yellowish to
         purple flowers; sometimes includes species often placed in
         genus Nabalus [syn: Prenanthes, genus Prenanthes]