pericarp vs epicarp

pericarp and epicarp both are nouns.

Word	Noun	Adjective	Verb	Adverb
pericarp	Yes	No	No	No
epicarp	Yes	No	No	No

As nouns, epicarp is a hyponym of pericarp; that is, epicarp is a word with a more specific, narrower meaning than pericarp:

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

Other hyponyms of pericarp include exocarp, mesocarp, endocarp, pit, stone, capsule, bur, burr.

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