relish vs devour

relish is a noun but devour is not a noun.

Word	Noun	Adjective	Verb	Adverb
relish	Yes	No	Yes	No
devour	No	No	Yes	No

As verbs, devour is a hyponym of relish; that is, devour is a word with a more specific, narrower meaning than relish:

relish: derive or receive pleasure from; get enjoyment from; take pleasure in
devour: enjoy avidly

Other hyponyms of relish include feast one's eyes.

relish (noun)	devour (noun)
the taste experience when a savoury condiment is taken into the mouth
vigorous and enthusiastic enjoyment
spicy or savory condiment

relish (verb)	devour (verb)
derive or receive pleasure from; get enjoyment from; take pleasure in	eat greedily
	eat up completely, as with great appetite
	to consume
	enjoy avidly