rattlesnake weed vs Hieracium venosum

rattlesnake weed and Hieracium venosum both are nouns.

Word	Noun	Adjective	Verb	Adverb
rattlesnake weed	Yes	No	No	No
Hieracium venosum	Yes	No	No	No

As nouns, rattlesnake weed and Hieracium venosum are synonyms defined as:

rattlesnake weed and Hieracium venosum: a hawkweed with a rosette of purple-veined basal leaves; Canada to northern Georgia and Kentucky

rattlesnake weed (noun)	Hieracium venosum (noun)
a hawkweed with a rosette of purple-veined basal leaves; Canada to northern Georgia and Kentucky	a hawkweed with a rosette of purple-veined basal leaves; Canada to northern Georgia and Kentucky