wild cabbage vs crucifer

wild cabbage and crucifer both are nouns.

Word	Noun	Adjective	Verb	Adverb
wild cabbage	Yes	No	No	No
crucifer	Yes	No	No	No

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

wild cabbage: wild original of cultivated cabbages; common in western coastal Europe
crucifer: any of various plants of the family Cruciferae

Other hypernyms of wild cabbage include cruciferous plant.

wild cabbage (noun)	crucifer (noun)
wild original of cultivated cabbages; common in western coastal Europe	any of various plants of the family Cruciferae