in-frēno (infraen-), āvi, ātum, 1, v. a., to put on a bridle. Lit., to furnish with a bridle, to bridle: equos, Liv. 37, 20, 12; cf.: non stratos, non infrenatos equos habere, ib. § 4: currus, to harness the horses to a chariot, Verg. A. 12, 287: infrenati manipli, on bridled horses, Sil. 4, 316.

— Transf., to curb, restrain: horum (ducum) alterum sic fuisse infrenatum conscientia scelerum, Cic. Pis. 19, 44: navigia ancoris, Plin. 9, 31, 51, § 100: infrenat impetus et domat mundi rabiem, id. 32, 1, 1, § 2: lascivias carnis, Ambros. in Luc. 9, § 8.