giant hogweed
noun
plural giant hogweeds
: a tall perennial herb (Heracleum mantegazzianum) of the carrot family native to the Caucasus that has a hollow, usually purple-blotched stem which can reach a height of 15 to 20 feet (4.6 to 6.1 meters) and white-flowered umbels arranged in flat-topped clusters usually over 2.5 feet (0.8 meters) in diameter and that produces an irritating sap that causes severe rashes and blistering
Note: The giant hogweed has become invasive in Canada and the U.S. after being introduced as an ornamental plant in the early 1900s.
She didn't realize she was planting poison. The plant was giant hogweed—a noxious, weed that looks like Queen Anne's lace and can give blistering, oozing rashes to anyone who touches its sap.—
Noreen Gillespie
Noreen GillespieGiant hogweed … stands eight feet tall displaying three-foot long coarsely divided leaves and stems crowned with huge parasols of small white flowers.—Taimi Anderson
Taimi Andersoncalled also cartwheel flower, giant cow parsley, giant cow parsnip, hogsbane
Examples of giant hogweed in a Sentence
Recent Examples on the Web
Another carrot cousin is giant hogweed, which has enormous blooms that look a bit like Queen Anne's lace on steroids.
—
Melissa Locker,
Southern Living,
22 June 2026
The best way to prevent giant hogweed rashes and burns is to learn how to identify it.
—
Natalie Krebs,
Outdoor Life,
26 Mar. 2026
Like the wild parsnip, giant hogweed contains sap that can cause a skin reaction when exposed to the sun.
—
Claire Reid,
Journal Sentinel,
8 Aug. 2023
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Melissa Locker,
Southern Living,
22 June 2026
The best way to prevent giant hogweed rashes and burns is to learn how to identify it.
—
Natalie Krebs,
Outdoor Life,
26 Mar. 2026
Like the wild parsnip, giant hogweed contains sap that can cause a skin reaction when exposed to the sun.
—
Claire Reid,
Journal Sentinel,
8 Aug. 2023
Cite this Entry
“Giant hogweed.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/giant%20hogweed. Accessed 6 Jul. 2026.
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