The Collaborative International Dictionary of English v.0.48:

Arceuthobium \Arceuthobium\ prop. n.
   A genus of chiefly American plants parasitic on conifers.

   Syn: genus Arceuthobium.
        [WordNet 1.5]

WordNet (r) 3.0 (2006):

Arceuthobium
    n 1: genus of chiefly American plants parasitic on conifers
         [syn: Arceuthobium, genus Arceuthobium]