Albert Barnes Commentary Joshua 14:15

"Now the name of Hebron beforetime was Kiriath-arba; [which Arba was] the greatest man among the Anakim. And the land had rest from war." — Joshua 14:15 (ASV)

A great man - literally, the great man; that is, the renowned ancestor of the tribe, regarded as the founder of its greatness (Joshua 15:13).