1N-COUNT [usually plural]下颌垂肉;(尤指)双下巴 You can refer to someone's lower cheeks as their jowls, especially when they hang down towards their jaw. 下颌垂肉;(尤指)双下巴 [literary]
2PHRASE 紧紧靠着;紧挨着 If you say that people or things are cheek by jowl with each other, you are indicating that they are very close to each other. 紧紧靠着;紧挨着
She and her family have to live cheek by jowl with these people. [+ with]