Lewis & Short

dĭārĭum, ii, n. [dies].

  1. I. A daily allowance of food or pay (so only in the plur.), Cic. Att. 8, 14; Hor. Ep. 1, 14, 40; Sen. Contr. 4, 27 fin.; cf. Charis. p. 21 P.
  2. * II. A diary, journal: diarium, quam Graeci ἐφημερίδα vocant, Asel. ap. Gell. 5, 18, 8; cf. Isid. Or. 1, 43, 1.