The headword biw=ntai is probably extracted from the quotation given (though it also occurs in Oppian, Cynegetica 2.510, where a scholiast glossed it with bia/zontai).
[1] [Polybius] fr. 121 Büttner-Wobst. For this verb, otherwise characteristic of epic poetry, see LSJ s.v. Büttner-Wobst notes that Schweighäuser attributed the fragment to Polybius, while Dindorf, on the other hand, rejected it (p. 530). Büttner-Wobst himself is skeptical about whether this fragment is genuinely Polybian, drawing attention (ibid.) to the divergent account of the Roman entry into Carthage at Polybius 36.7.5 (web address 1).