cheek
 /ˈʧiːk/  noun  ,  pl   cheeks
  1 [  count  ] : the part of the face that is below the eye and to the side of the nose and mouth
   rosy/chubby cheeks
   He kissed her on the cheek.
   They were sitting/dancing/posing cheek to cheek. [=with their cheeks touching]
  — see also tongue in cheek
  2 Brit : an attitude or way of behaving that is rude and does not show proper respect
   [  noncount  ] He had the cheek [=nerve] to complain that our gift was cheap.
   [  singular  ] He's got a cheek ignoring us like that.
  3 [  count  ] informal : one of the two parts of the body that a person sits on : buttocks
  cheek by jowl
   : very close together
    We sat cheek by jowl [=side by side] with the city's elite.
    cheap knickknacks displayed cheek by jowl with fine antiques
  turn the other cheek
   : to choose not to try to hurt or insult someone who has hurt or insulted you