Job 15:26. He runneth upon him, even on his neck, upon the thick bosses of his bucklers.
The boss was the external convex part of the round shield, its thickest and strongest portion. There were some shields whose shape was wholly convex, the center being an elevated point, as may be seen in the engraving, which represents an Assyrian convex shield.
There were also convex ornaments which were placed on the outside of shields, adding strength as well as beauty. Layard found at Nimrod circular bronze shields, each having an iron handle fastened by six nails. The heads of these nails formed bosses on the outside of the shield.
In the text Eliphaz expresses the uselessness of the attack which the wicked man makes on God, by representing him as running upon the most impenetrable part of the shield.