: a biennial Eurasian thistle (Cirsium vulgare) with purplish flower heads and prickly leaves that is naturalized as a weed in the U.S.
Example Sentences
Recent Examples on the WebErrol’s rolling links, which once had lush greens and fairways, are now dry and brown and pocked by bull thistles and other prickly weeds. Stephen Hudak, OrlandoSentinel.com, 18 Apr. 2018