tendril vs plant structure

tendril and plant structure both are nouns.

Word	Noun	Adjective	Verb	Adverb
tendril	Yes	No	No	No
plant structure	Yes	No	No	No

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

tendril: slender stem-like structure by which some twining plants attach themselves to an object for support
plant structure: any part of a plant or fungus

Other hypernyms of tendril include plant part.

tendril (noun)	plant structure (noun)
slender stem-like structure by which some twining plants attach themselves to an object for support	any part of a plant or fungus