Chinese cabbage vs crucifer

Chinese cabbage and crucifer both are nouns.

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

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

Chinese cabbage: plant with an elongated head of broad stalked leaves resembling celery; used as a vegetable in east Asia
crucifer: any of various plants of the family Cruciferae

Other hypernyms of Chinese cabbage include cruciferous plant.

Chinese cabbage (noun)	crucifer (noun)
elongated head of crisp celery-like stalks and light green leaves	any of various plants of the family Cruciferae
plant with an elongated head of broad stalked leaves resembling celery; used as a vegetable in east Asia