From riyb; literally, he will contend; properly, adjective, contentious; used as noun, an adversary -- that content(-eth), that strive.
see HEBREW riyb
H3401. yarib
I. [יָרִיב] noun [masculine] opponent, adversary (Ges§ 85d); — suffix (of Zion), יְדִיבֵךְ Isaiah 49:26 (רִיבֵךְ ᵐ5 so Du); compare plural suffix יְרִיבַ֑י Psalm 35:1 ("" לֹחֲמָ֑י); of personal opponent, יְרִיבָ֑י Jeremiah 18:19 (דִיבִי ᵐ5, so Gie).