Veronica peregrina vs veronica

Veronica peregrina and veronica both are nouns.

Word	Noun	Adjective	Verb	Adverb
Veronica peregrina	Yes	No	No	No
veronica	Yes	No	No	No

As nouns, veronica is a hypernym of Veronica peregrina; that is, veronica is a word with a broader meaning than Veronica peregrina:

Veronica peregrina: North American annual with small white flowers widely naturalized as a weed in South America and Europe
veronica: any plant of the genus Veronica

Other hypernyms of Veronica peregrina include speedwell.

Veronica peregrina (noun)	veronica (noun)
North American annual with small white flowers widely naturalized as a weed in South America and Europe	any plant of the genus Veronica