Lewis & Short

frēnum or fraenum, i, n., and more freq. (cf. Neue, Formenl. 1, 567; and v. infra), plur. heterocl. frēni, ōrum, m., and mostly poet. frēna, ōrum, n. [root dhar-; Sanscr. dhar-ā-mi, hold, support; Gr. θρα-, in θρῆνυς, θρόνος; Lat. frētus], a bridle, curb, bit (syn.: lupi, lupata).

  1. I. Lit.
          1. (α) Plur.: aurei freni, Curt. 4, 13 med.; so nom. freni, id. 7, 10 fin.; cf. under II.; acc. frena, Verg. A. 4, 135; 5, 818; Ov. M. 15, 519; id. Am. 3, 4, 16: non domito frenos ore momordit equus, Tib. 1, 3, 42; so, frenos: equus, equa, quae frenos recipere solet, Cic. Top. 8, 36; Varr. R. R. 2, 7, 12; Verg. G. 3, 184; Liv. 1, 48, 6; Sen. Tranq. 15 fin. al.: moderarier hunc (equum) frenis, Lucr. 5, 1298; so, frenis, id. 5, 1317; Verg. A. 11, 719; 889; 12, 372; Hor. S. 1, 1, 91; Ov. M. 5, 643; Liv. 1, 14 fin.: equum cogere frenos pati, Phaedr. 4, 3, 9: frenos et strata equorum Pelethronium (invenisse), Plin. 7, 56, 57, § 202 et saep.
          2. (β) Sing.: frenumque (equus) recepit, etc., Hor. Ep. 1, 10, 36: non frenum depulit ore, id. ib. 1, 10, 38.
        1. b. Prov.: frenum mordere, to take the bit in one’s teeth, i. e. to offer opposition, to resist: si frenum momorderis peream, Brut. ap. Cic. Fam. 11, 23, 2; cf.: sed ut mones, frenum momordi, Cic. ib. 11, 24, 1.
  2. II. Transf.
    1. A. Like our terms bridle and curb, i. q. means of guiding or governing, restraint, check, limit.
          1. (α) Plur.: rerum freni, the reins of dominion, Sil. 1, 240: freni sunt injecti vobis, Quirites, nullo modo perpetiendi: alligati et constricti estis amaro vinculo servitutis, Val. Max. 2, 9, 5; cf.: freni domitarum gentium, Curt. 7, 10 fin.: ne Lycurgi quidem disciplina tenuit illos in hominibus Graecis frenos, Cic. Rep. 2, 33: ut Isocratem in acerrimo ingenio Theopompi et lenissimo Ephori dixisse traditum est, alteri se calcaria adhibere, alteri frenos, id. Brut. 56, 204: Mutinam illi exsultanti tamquam frenos furoris injecit, id. Phil. 13, 9, 20: date frenos impotenti naturae et indomito animali, give the reins to, allow full scope to, Liv. 34, 2, 13; so, frenos furentibus ira Laxat, Luc. 7, 125: impone felicitati tuae frenos, put on, Curt. 7, 8 fin.: imperii frena tenere sui, Ov. Tr. 2, 42: frena imperii moderari, id. P. 2, 9, 33: capere, id. ib. 4, 13, 27: frena licentiae inicere, Hor. C. 4, 15, 10: pone irae frena modumque, Pone et avaritiae, Juv. 8, 88: subiit leges et frena momordit Ille solutus amor, i. e. submitted to, Stat. S. 1, 2, 28: quod dicebat Isocrates, se calcaribus in Ephoro, contra autem in Theopompo frenis uti solere, Cic. de Or. 3, 9, 36; Quint. 2, 8, 11; cf. above the passage Cic. Brut. 56, 204: alter, uti dixit Isocrates in Ephoro et Theopompo, frenis eget, alter calcaribus, id. Att. 6, 1, 12: non solum frenis sed etiam jugo accepto, Liv. 37, 36, 5: animum rege: qui nisi paret, Imperat: hunc frenis, hunc tu compesce catenā, Hor. Ep. 1, 2, 63: jam vaga prosiliet frenis natura remotis, id. S. 2, 7, 74.
          2. (β) Sing.: ni frenum accipere et victi parere fatentur, Verg. A. 12, 568: voluptates tenere sub freno, Sen. Ep. 23 med.
    2. B. Poet., horse, steed, charger: eques aptus frenis, Prop. 4 (5), 10, 19: portarumque moras frenis assultat et hastis, Stat. Th. 11, 243.
    3. C. In gen.
      1. 1. That which holds things together, a band (post-Aug. and rare): absiliunt pontes tectique trementis Saxea frena labant, etc., the stone bands, ties, Stat. Th. 10, 880.
      2. 2. In anatomy: frenum, the ligament which attaches the inside of the foreskin to the glans, Cels. 7, 25, 2.