cheek vs buttock

cheek and buttock both are nouns.

Word	Noun	Adjective	Verb	Adverb
cheek	Yes	No	Yes	No
buttock	Yes	No	No	No

As nouns, cheek and buttock are synonyms defined as:

cheek and buttock: either of the two large fleshy masses of muscular tissue that form the human rump

cheek (noun)	buttock (noun)
impudent aggressiveness	either of the two large fleshy masses of muscular tissue that form the human rump
either side of the face below the eyes
either of the two large fleshy masses of muscular tissue that form the human rump
an impudent statement

cheek (verb)	buttock (verb)
speak impudently to