onion vs alliaceous plant

onion and alliaceous plant both are nouns.

Word	Noun	Adjective	Verb	Adverb
onion	Yes	No	No	No
alliaceous plant	Yes	No	No	No

As nouns, alliaceous plant is a hypernym of onion; that is, alliaceous plant is a word with a broader meaning than onion:

onion: bulbous plant having hollow leaves cultivated worldwide for its rounded edible bulb
alliaceous plant: bulbous plants having a characteristic pungent onion odor

onion (noun)	alliaceous plant (noun)
an aromatic flavorful vegetable	bulbous plants having a characteristic pungent onion odor
bulbous plant having hollow leaves cultivated worldwide for its rounded edible bulb
the bulb of an onion plant