וּלְדָ֣ן אָמַ֔ר דָּ֖ן גּ֣וּר אַרְיֵ֑ה יְזַנֵּ֖ק מִן־הַבָּשָֽׁן׃
און אױף דָן האָט ער געזאָגט:דָן איז אַ יונגער לײב, ער שפּרינגט פֿון בשָן אַרױס.
Rashi
דן גור אריה DAN IS A LION’S CUB — He, too, lived close to the border, and therefore it compares him to a lion (Sifrei Devarim 355:12).
Chizkuni
יזנק מן הבשן, “he leaps forth from the region of Bashan.” He (Dan) conquers in that region, although it is well known as the habitat of lions and other ferocious beasts.
Da'at Zekenim
דן גור אריה, “Dan is a lion’s whelp;” he is described as such as its troops were constantly standing guard along the borders, making sure no enemy forces would cross into the Israelites’ territory.