sweet clover vs woody plant

sweet clover and woody plant both are nouns.

Word	Noun	Adjective	Verb	Adverb
sweet clover	Yes	No	No	No
woody plant	Yes	No	No	No

As nouns, woody plant is a hypernym of sweet clover; that is, woody plant is a word with a broader meaning than sweet clover:

sweet clover: erect annual or biennial plant grown extensively especially for hay and soil improvement
woody plant: a plant having hard lignified tissues or woody parts especially stems

Other hypernyms of sweet clover include ligneous plant.

sweet clover (noun)	woody plant (noun)
erect annual or biennial plant grown extensively especially for hay and soil improvement	a plant having hard lignified tissues or woody parts especially stems