Lewis & Short

ŏb-ĭter, adv., on the way, in going or passing along (except in Laber., not anteAug.; cf. Charis. 187 P. Augustus found fault with Tiberius for using per viam instead of obiter, Charis. l. l.).

  1. I. Lit.: obiter leget aut scribet, on the way, Juv. 3, 241: rotae, quas aqua verset obiter et molat, as it flows along, Plin. 18, 10, 23, § 97; cf. id. 33, 4, 21, § 74; 29, 3, 11, § 48; 11, 37, 55, § 148.
  2. II. Transf.
    1. A. By the way, in passing, incidentally: interrogo ego: Quot estis? obiterque per rimam speculari coepit, Petr. 92: faciem linit, Juv. 6, 481: ne in hoc quidem tam molesto tacebant officio, sed obiter cantabant, Petr. 31: saevire, Sen. Ira, 3, 1, 3: licet obiter vanitatem magicam hic quoque coarguere, Plin. 37, 9, 37, § 118: dictum sit, id. 29, 5, 30, § 96; 29, 1, 9, § 29; Dig. 18, 5, 1 fin.
    2. B. Forthwith, straightway, immediately (very rare): ἐν τῷ αὐτῷ inibi, obiter, Gloss. Philox.: reducant, App. M. 6, p. 183, 35: ut obiter revertantur, Auct. Quint. Decl. 10, 16 fin.