Arba is the father of Anak. He may have been a literal father, or he may have been the leader of the descendants of Anak, meaning the giant race.
Josh 14:15The former name of Hebron was Kiriath-arba; this Arba was the greatest man among the Anakim. Then the land had rest from war.
Josh 15:13According to the Lord’s command to Joshua, Joshua gave Caleb son of Jephunneh a portion among the people of Judah—Kiriath-arba, that is, Hebron. (Arba was the father of Anak.)
He is believed to have founded Kiriath-arba, which is Hebron.
Josh 21:11They gave them Kiriath-arba (that is, Hebron), with its surrounding pasturelands, in the hill country of Judah. (Arba was the father of Anak.)
Two of David's mighty men are referred to as Arba-ites, but it is unclear whether they were his descendants or if it refers to a specific place.
1 Chr 11:32Hurai of the ravines of Gaash, Abiel the Arbathite,
2 Sam 23:31Abi-albon the Arbathite, Azmaveth the Barhumite,