Lewis & Short

dĭurnus, a, um, adj. [for dius-nus, from dies; cf.: interdius, quotidianus, etc.], of or belonging to the day.

  1. I. In a wider sense, daily (perh. not ante-Aug.): aetatis fata diurna, i. e. of only one day, Ov. H. 6, 37: instituit, ut tam Senatus quam populi diurna acta confierent et publicarentur, daily transactions, records, journal, Suet. Caes. 20; Tac. A. 13, 31; Suet. Claud. 41 Oud. N. cr.; in the same signif.: commentarii, id. Aug. 64; cf. also: diurna actorum scriptura, Tac. A. 3, 3. (Concerning these acta diurna, v. Lips. Exc. ad Tac. A. 5, 4; Ernest. Exc. ad Suet. Caes. 20; Rupert. ad Juv. 2, 136; Walch ad Tac. Agr. p. 114, and the art. acta): cibus, daily allowance, rations, Liv. 4, 12 fin.: victus, Suet. Ner. 36 fin.: mercede diurna conductus, Hor. S. 2, 7, 17.
    Hence, subst.
    1. A. diurnum, i, n., an account-book, day-book: longum, Juv. 6, 482; plur. (sc. acta), diaries, records, minutes: diurna populi Romani, per provincias curatius leguntur, Tac. A. 16, 22.
      Also subst.
    2. B. diurnum, i, n. (sc. frumentum), a daily portion, allowance, rations (cf. diarium), Sen. Ep. 80, 8; id. Contr. 5, 33 fin.; cf. Suet. Ner. 30.
  2. II. In a stricter sense (acc. to dies, I. B. 2.), opp. nocturnus, by day, of the day (very freq. and class.): diurnum nocturnumve spatium, Cic. Inv. 1, 26, 39: labores diurni nocturnique, id. de Sen. 23, 82; cf. so opp. nocturnus, Lucr. 6, 849; Cic. Off. 3, 21, 84; id. Tusc. 1, 21, 48; Caes. B. G. 1, 38 fin.; id. B. C. 3, 13, 1; Quint. 7, 2, 44; Hor. Ep. 1, 19, 11; Ov. F. 3, 878 et saep.: lumen, Lucr. 4, 458; so Ov. F. 4, 449; cf. stella, i. e. the morning-star, Plaut. Men. 1, 2, 62: currus, i. e. the chariot of the sun, Ov. M. 4, 629: ignes, id. ib. 7, 192: nitor, id. H. 18, 78 al.: actus, the day’s business, Suet. Aug. 78.
    Adv.: dĭurne, daily, Dracont. Hex. 1, 68; 3, 602.