Helkath-Hazzurim
Helkath-hazzurim is the name fixed to a patch of ground at Gibeon after a set-piece combat between Abner's men and Joab's men. The text supplies the naming etiology in a single verse.
The Combat at the Pool of Gibeon
Two armies meet across the pool, Abner from Mahanaim with the men of Ishbaal, and Joab with the men of David: "they sat down, the one on the one side of the pool, and the other on the other side of the pool" (2Sa 2:13). Abner proposes a contest of young men, twelve for each side, and Joab agrees (2Sa 2:14-15).
The Naming of the Ground
The combat is mutually fatal. "And they caught every one his fellow man by the head, and [thrust] his sword in his fellow man's side; so they fell down together: therefore that place was called Helkath-hazzurim, which is in Gibeon" (2Sa 2:16). The site name is etiological — fixed to the spot where the twenty-four picked men fell together — and the wider engagement that followed only deepened the day's casualties before Abner was driven back (2Sa 2:17).