mustard vs genus Brassica

mustard and genus Brassica both are nouns.

Word	Noun	Adjective	Verb	Adverb
mustard	Yes	No	No	No
genus Brassica	Yes	No	No	No

mustard (noun)	genus Brassica (noun)
pungent powder or paste prepared from ground mustard seeds	mustards: cabbages, cauliflowers, turnips, etc.
leaves eaten as cooked greens
any of several cruciferous plants of the genus Brassica