Definitions for "Tarweed"
A name given to several resinous-glandular composite plants of California, esp. to the species of Grindelia, Hemizonia, and Madia.
any of various resinous glandular plants of the genus Madia; of western North and South America
any of various western American plants of the genus Grindelia having resinous leaves and stems formerly used medicinally; often poisonous to livestock