(1 Samuel 17:4, 23), properly "the man between the two," denoting the position of Goliath between the two camps. Single combats of this kind at the head of armies were common in ancient times. In ver. 51 this word is the rendering of a different Hebrew word, and properly denotes "a mighty man."

Noah Webster's New International Dictionary of the English Language

(v. t.) To furnish with a champion; to attend or defend as champion; to support or maintain; to protect.