Arceuthobium ar·ceut·ho·bium uncommon noun 1. genus of chiefly American plants parasitic on conifers Synonymsgenus Arceuthobium Related words Word family Arceuthobium pusillum Broader terms dilleniid dicot genus Parts Loranthaceae Part of American mistletoe WordNet 2.1 (Princeton University). WordNet 2.1 Copyright Princeton University. All rights reserved.