herbs robert vs herb roberts

herbs robert and herb roberts both are nouns.

Word	Noun	Adjective	Verb	Adverb
herbs robert	Yes	No	No	No
herb roberts	Yes	No	No	No

As nouns, herbs robert and herb roberts are synonyms defined as:

herbs robert and herb roberts: a sticky low herb with small reddish-purple flowers; widespread in the Northern Hemisphere

Other synonyms of herbs robert include Geranium robertianum, herb robert.

herbs robert (noun)	herb roberts (noun)
a sticky low herb with small reddish-purple flowers; widespread in the Northern Hemisphere	a sticky low herb with small reddish-purple flowers; widespread in the Northern Hemisphere