parsnip vs Pastinaca sativa

parsnip and Pastinaca sativa both are nouns.

Word	Noun	Adjective	Verb	Adverb
parsnip	Yes	No	No	No
Pastinaca sativa	Yes	No	No	No

As nouns, parsnip and Pastinaca sativa are synonyms defined as:

parsnip and Pastinaca sativa: a strong-scented plant cultivated for its edible root

parsnip (noun)	Pastinaca sativa (noun)
whitish edible root; eaten cooked	a strong-scented plant cultivated for its edible root
a strong-scented plant cultivated for its edible root
the whitish root of cultivated parsnip