an umbelliferous garden escape, Heracleum mantegazzianum, a tall species of cow parsley that grows up to 31⁄2 metres (10 ft) and whose irritant hairs and sap can cause a severe reaction if handled
Also called: cartwheel flower
Examples of 'giant hogweed' in a sentence
giant hogweed
There is also a giant hogweed that grows to twice that size.
Times, Sunday Times (2015)
The giant hogweed has beautiful flowers but its sap is extremely toxic.
The Sun (2011)
Giant hogweed is growing up in colonies here and there.