C. F. Keil and Franz Delitzsch on Genesis 32:25

Gen 32:25

When Jacob was left alone on the northern side of the Jabbok, after sending all the rest across, “there wrestled a man with him until the breaking of the day.” נאבק, an old word, which only occurs here (Gen 32:25, Gen 32:26), signifying to wrestle, is either derived from אבק to wind, or related to חבק to contract one’s self, to plant limb and limb firmly together. From this wrestling the river evidently received its name of Jabbok (יבּק = יאבּק).