viper's bugloss vs Echium vulgare

viper's bugloss and Echium vulgare both are nouns.

Word	Noun	Adjective	Verb	Adverb
viper's bugloss	Yes	No	No	No
Echium vulgare	Yes	No	No	No

As nouns, viper's bugloss and Echium vulgare are synonyms defined as:

viper's bugloss and Echium vulgare: a coarse prickly European weed with spikes of blue flowers; naturalized in United States

Other synonyms of viper's bugloss include blue devil, blue thistle, blueweed.

viper's bugloss (noun)	Echium vulgare (noun)
a coarse prickly European weed with spikes of blue flowers; naturalized in United States	a coarse prickly European weed with spikes of blue flowers; naturalized in United States