tepal vs plant structure

tepal and plant structure both are nouns.

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

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

tepal: an undifferentiated part of a perianth that cannot be distinguished as a sepal or a petal (as in lilies and tulips)
plant structure: any part of a plant or fungus

Other hypernyms of tepal include plant part.

tepal (noun)	plant structure (noun)
an undifferentiated part of a perianth that cannot be distinguished as a sepal or a petal (as in lilies and tulips)	any part of a plant or fungus