aralia vs ligneous plant

aralia and ligneous plant both are nouns.

Word	Noun	Adjective	Verb	Adverb
aralia	Yes	No	No	No
ligneous plant	Yes	No	No	No

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

aralia: any of various plants of the genus Aralia; often aromatic plants having compound leaves and small umbellate flowers
ligneous plant: a plant having hard lignified tissues or woody parts especially stems

Other hypernyms of aralia include woody plant.

aralia (noun)	ligneous plant (noun)
any of various plants of the genus Aralia; often aromatic plants having compound leaves and small umbellate flowers	a plant having hard lignified tissues or woody parts especially stems