Canada thistle

American  

noun

1. an Old World plant, Cirsium arvense, having small purple or white flower heads, now a troublesome weed in North America.

---

Canada thistle British  

noun

1. the US and Canadian name for creeping thistle

---

Etymology

Origin of Canada thistle

An Americanism dating back to 1790–1800

Example Sentences

Today, 140 years later, Canada thistle is a Class C noxious weed in Washington.

From Seattle Times • Jun. 11, 2022

Many look for nectar on dandelion, rabbitbrush, Canada thistle, osier dogwood and chokecherry.

From Seattle Times • Aug. 27, 2021

They are targeting Johnson grass, giant foxtail, Canada thistle, nodding thistle, common teasel, multiflora rose, Amur honeysuckle, poison hemlock, marestail, Japanese knotweed and kudzu.

From Washington Times • Mar. 18, 2021

The state’s contractor, Ed’s Plant World of Brandywine, is going after porcelain-berry, kudzu, Canada thistle and mile-a-minute weed, among other species.

From Washington Post • Aug. 27, 2016

Examples: the roots of dahlia, rhubarb, dandelion, and chicory; the underground stems of potato, onion, tulip, scutch-grass, Canada thistle, etc.

From Ontario Teachers' Manuals: Nature Study by Ontario. Ministry of Education