ゆさゆさする

(1)move back and forth or sideways; "the ship was rocking"; "the tall building swayed"; "She rocked back and forth on her feet"

(2)前後または横に動く

(3)cause to move back and forth; "rock the cradle"; "rock the baby"; "the wind swayed the trees gently"

(4)前後に動く理由

(1)