Lewis & Short

rĕtĭnācŭlum (sync. retinaclum, Prud. ap. Symm. 2, 147), i, n. [retineo, I.], that which holds back or binds; a holdfast, band, tether, halter, halser, rope, cable (only in plur.; but the sing. occurs as v. l. Amm. 30, 4, 4).

  1. I. Lit., Cato, R. R. 63; 135, 5; Liv. 21, 28; Col. 4, 13, 1; 6, 2, 4; Vitr. 10, 5; Verg. G. 1, 265; 513; id. A. 4, 580; Hor. S. 1, 5, 18; Ov. M. 8, 102; 11, 712; 14, 547; Stat. S. 3, 2, 32.
  2. II. Trop., a bond, chain, tie: vita abrupit, Plin. Ep. 1, 12, 8: desiderii, App. M. 11, p. 269, 28 (p. 806 Oud.): blanda morarum, Aus. Ep. 8, 1: leges, fundamenta libertatis et retinacula sempiterna, Amm. 14, 6, 5: retinaculis temporis praestituti frenari, id. 30, 4, 4.