Cheek
WordNet
noun
(1) Impudent aggressiveness
"I couldn't believe her boldness"
"He had the effrontery to question my honesty"
(2) Either of the two large fleshy masses of muscular tissue that form the human rump
(3) Either side of the face below the eyes
(4) An impudent statement
verb
(5) Speak impudently to