cookie vs wafer

cookie and wafer both are nouns.

Word	Noun	Adjective	Verb	Adverb
cookie	Yes	No	No	No
wafer	Yes	No	No	No

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

cookie (noun)	wafer (noun)
a short line of text that a web site puts on your computer's hard drive when you access the web site	a small thin crisp cake or cookie
any of various small flat sweet cakes	thin disk of unleavened bread used in a religious service (especially in the celebration of the Eucharist)
the cook on a ranch or at a camp	a small adhesive disk of paste; used to seal letters