- gumweed, gum plant, tarweed, rosinweed - any of various western American plants of the genus Grindelia having resinous leaves and stems formerly used medicinally; often poisonous to livestock
--1 is a kind of herb, herbaceous plant
--1 is a member of Grindelia, genus Grindelia
--1 has particulars: Grindelia robusta; curlycup gumweed, Grindelia squarrosa