Lewis & Short

1. rĕtento, āvi, ātum, 1, v. freq. a. [retineo], to hold back firmly, to keep back, to hold fast (rare; not in Cic.).

  1. I. Lit.: cur me retentas? Plaut. As. 3, 3, 1; id. Rud. 3, 6, 39; cf. agmen, Liv. 10, 5: legiones, Tac. H. 4, 13: fugientes, id. ib. 5, 21: admissos equos, Ov. A. A. 2, 434; cf. frena, id. Am. 2, 9, 30: puppes, Tac. H. 2, 35; Luc. 3, 586: vires regni, id. 4, 723: pecuniam, calones, sarcinas, Tac. H. 4, 60: caelum a terris, i. e. to hold apart, Lucr. 2, 729: iste qui retentat sese tacitus, quo sit tutus, restrains himself, Auct. Her. 4, 49, 62.
  2. II. Trop.: iras, i. e. to suppress, Val. Fl. 3, 97.
    1. B. Transf., to hold back from destruction, preserve, maintain: (mens divina) Quae penitus sensus hominum vitasque retentat, Cic. poët. Div. 1, 11, 17.

2. rĕ-tento (-tempto), āvi, ātum, 1, v. a., to try or attempt again, to reattempt (a poet. word of the Aug. per.): timide verba intermissa retentat, Ov. M. 1, 746: preces, id. ib. 14, 382: fila lyrae, id. ib. 5, 117: referoque manus iterumque retento, id. H.10,11: viam leti, id. M. 11, 792: studium fatale, id. Tr. 5, 12, 51: arma, Luc. 2, 514: memoriam meam, Sen. Ep. 72, 1: nec audent ea retentare, quorum vitia retractando patescunt, id. Brev. Vit. 10, 2: nec vana retentet spes Minyas, move or affect again, Val. Fl. 5, 679.
With inf.: saepe retentantem totas refringere vestes, Ov. M. 9, 208.