Rashi: Because they too, like Gad, ¹ dwelled on the border [and guarded Yisrael from enemies

Rashi #1 (citing Targum Onkelos) and Targum Yonasan: It refers to the River Yarden, which originates from the Bashan, and flows from the Banyas Cave, otherwise known as 'Leshem', which is situated in the portion of Dan. ¹

Rashi #2: Just as 'Zinuk' refers to a river that flows from one location but splits into two, so too, is the tribe of Dan destined to receive their portion in two places - first in the north-west, in Ekron and its environs, and later they fought and captured Leshem, ² in the north-east of the country, which is synonymous with Banyas, from which the Yarden flows.

Rashi #3 (on the explnation of 'ha'Kalir', which is attributed to Rashi): 'Which flows from the mountain of Bashan in the rain season and enabling the grass and vegetation which were planted there to feed the calves.

Seforno: It means that Dan (the lion-cub) will spring from the Bashan, a choice area for grazing sheep and cattle ³ - and from where a lion will not spring, unless it knows for sure that it will catch its prey; so too, will Dan be sure that, when they attack, they will destroy the enemy.

Da'as Zekenim and Rosh: The Yarden separates between Bashan (Og's region, which Gad received) and Dan (which was on the west bank. ⁴