Sentence:  But be careful what you are about, for overhead is the terrible "Laportea crenulata", or <WSD>devil's nettle</WSD>; the petioles of the leaves are hispid with poisonous hairs, the sting of which, once felt, will not be forgotten by you in a hurry; 
Meaning of the word marked with <WSD> tags:  (species) (synonym: "Laportea crenulata"), a species of nettle in the family Urticaceae found in Australia and South Asia.