Lewis & Short

2. discessus, ūs, m. [discedo].

  1. I. A going asunder, separation, opening (very rare): caeli, i. e. lightning, Cic. Div. 2, 28, 60: est interitus quasi discessus et secretio ac diremptus earum partium, quae ante interitum junctione aliqua tenebantur, id. Tusc. 1, 29, 71.
  2. II. A going away, departure, removal.
    1. A. In gen. (class.): ut me levarat tuus adventus, sic discessus afflixit, Cic. Att. 12, 50: subitus (with praeceps profectio), Att. ap. Cic. Att. 9, 10, 6: ab urbe, Cic. ib. 8, 3, 3: praeclarus e vita, id. Div. 1, 23, 47; cf. id. de Sen. 23: latronis, id. Phil. 5, 11, 30; cf. ceterorum, id. Cat. 1, 3, 7: legatorum, Caes. B. G. 7, 5 fin.: discessu mugire boves, Verg. A. 8, 215 al.
      In plur.: solis accessus discessusque, Cic. N. D. 2, 7, 19.
    2. B. In partic.
      1. 1. In milit. lang., a marching away, marching off, decamping, Caes. B. G. 2, 14, 1; 4, 4, 6; 7, 20, 1 et saep.; Tac. A. 2, 44; Front. Strat. 1, 1, 9; 1, 5, 25 al.
      2. 2. In Cic. applied to his banishment from Rome: cum, discessu meo, religionum jura polluta sunt, Cic. Leg. 2, 17, 42 (cf. absum); so id. de domo 32, 85.