crucifer vs herb

crucifer and herb both are nouns.

Word	Noun	Adjective	Verb	Adverb
crucifer	Yes	No	No	No
herb	Yes	No	No	No

As nouns, herb is a hypernym of crucifer; that is, herb is a word with a broader meaning than crucifer:

crucifer: any of various plants of the family Cruciferae
herb: a plant lacking a permanent woody stem; many are flowering garden plants or potherbs; some having medicinal properties; some are pests

Other hypernyms of crucifer include herbaceous plant.

crucifer (noun)	herb (noun)
any of various plants of the family Cruciferae	aromatic potherb used in cookery for its savory qualities
	a plant lacking a permanent woody stem; many are flowering garden plants or potherbs; some having medicinal properties; some are pests