Lewis & Short

fluctŭo, āvi, ātum, or (perh. not anteAug.) fluctŭor, ātus, 1 (pleraque utroque modo efferuntur: fluctuatur, fluctuat, Quint. 9, 3, 7), v. n. [fluctus], to move in the manner of waves, i. e. to wave, rise in waves, undulate, to move to and fro, be driven hither and thither (class.; esp. freq. in the trop. signif.; cf.: fluo, fluito).

  1. I. Lit.
          1. (α) Form fluctuo: nunc valide fluctuat mare, Plaut. Rud. 2, 1, 14: ita fluctuare video vehementer mare, id. ib. 4, 1, 12; 4, 2, 11: quadriremem in salo fluctuantem reliquerat, Cic. Verr. 2, 5, 35, § 91: quid tam commune quam mare fluctuantibus, litus ejectis? id. Rosc. Am. 26, 72: agebatur huc illuc Galba vario turbae fluctuantis impulsu, Tac. H. 1, 40; cf. Gell. 10, 6, 2: fluctuet aër, Lucr. 6, 367: directaeque acies ac late fluctuat omnis Aere renidenti tellus, waves (in the light) with gleaming brass, Verg. G. 2, 281: fluctuant insulae, Plin. 2, 95, 96, § 209: seges, Sen. Herc. Fur. 699.
            In mal. part., Arn. 2, 73; Auct. Priap. 19, 4; cf. fluctus, I.
          2. (β) Form fluctuor: deprehensi in mari Syrtico modo in sicco relinquuntur, modo fluctuantur, are driven about by the waves, Sen. Vit. Beat. 14: Delos diu fluctuata, Plin. 4, 12, 22, § 66: quaedam insulae semper fluctuantur, id. 2, 94, 95, § 209 Jan.: lignum in longitudinem fluctuatur, i. e. floats about, id. 16, 38, 73, § 186: lapidem e Scyro insula integrum fluctuari tradunt, eundem comminutum mergi, id. 36, 16, 26, § 130.
  2. II. Trop., to be restless, unquiet, uncertain, doubtful; to rage, swell; to waver, hesitate, vacillate, fluctuate.
          1. (α) Form fluctuo: Eu. Potin, ut animo sis tranquillo? Ch. Quid si animus fluctuat? Plaut. Merc. 5, 2, 49; cf.: animo nunc huc, nunc fluctuat illuc, Verg. A. 10, 680: mens animi tantis fluctuat ipsa malis, Cat. 65, 4: magnis curarum fluctuat undis, id. 64, 62; cf.: magnoque irarum fluctuat aestu, Verg. A. 4, 532; Anthol. Lat. 1, 178, 150: fluctuat ira intus, Verg. A. 12, 527: irarum fluctuat aestu, id. ib. 4, 564; so, curarum, 8, 19; Lucr. 4, 1077; Cat. 64, 62: ingenti Telamon fluctuat ira, Val. Fl. 3, 637: fluctuante rege inter spem metumque, Liv. 42, 59, 8: totam aciem suo pavore fluctuantem, etc., Curt. 3, 10, 6: in suo decreto, Cic. Ac. 2, 9, 29: fluctuantem sententiam confirmare, id. Att. 1, 20, 2: genus orationis, quod appellamus fluctuans et dissolutum, eo quod sine nervis et articulis fluctuat huc et illuc, Auct. Her. 4, 11, 16: omnia et citata et fluctuantia, Sen. Contr. 3, 19.
          2. (β) Form fluctuor: utrius populi mallet victoriam esse, fluctuatus animo fuerat, Liv. 23, 33, 3: fluctuatus animo est, utrum, etc., id. 32, 13, 4; 36, 10, 4; Curt. 4, 12, 21; Val. Max. 8, 1, 2: vita fluctuatur per adversa et difficilia, Sen. Ep. 111: semper inter spem et metum fluctuari, Aug. ap. Suet. Claud. 4: ambrosia (herba) vagi nominis est et circa alias herbas fluctuati, Plin. 27, 4, 11, § 28.