cook vs roaster

cook and roaster both are nouns.

Word	Noun	Adjective	Verb	Adverb
cook	Yes	No	Yes	No
roaster	Yes	No	No	No

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

Other hyponyms of cook include chef, cookie, cooky, fry cook, preserver, seasoner.

cook (noun)	roaster (noun)
someone who cooks food	a special cooking pan for roasting
	flesh of a large young chicken over 3 1/2 lb suitable for roasting
	a cook who roasts food
	a harsh or humorous critic (sometimes intended as a facetious compliment)

cook (verb)	roaster (verb)
transform and make suitable for consumption by heating
transform by heating
prepare for eating by applying heat
prepare a hot meal
tamper, with the purpose of deception