exocarp vs seed vessel

exocarp and seed vessel both are nouns.

Word	Noun	Adjective	Verb	Adverb
exocarp	Yes	No	No	No
seed vessel	Yes	No	No	No

As nouns, seed vessel is a hypernym of exocarp; that is, seed vessel is a word with a broader meaning than exocarp:

exocarp: outermost layer of the pericarp of fruits as the skin of a peach or grape
seed vessel: the ripened and variously modified walls of a plant ovary

Other hypernyms of exocarp include pericarp.

exocarp (noun)	seed vessel (noun)
outermost layer of the pericarp of fruits as the skin of a peach or grape	the ripened and variously modified walls of a plant ovary