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umbrōsus, a, um, adj. [umbra], full of shade, shady, umbrageous (class.; cf. opacus): locus umbrosior, Cic. Q. Fr. 3, 1, 2, § 3: fere aquosissima sunt quaecumque umbrosissima, Sen. Q. N. 3, 11, 4: fico folium maximum umbrosissimumque, Plin. 16, 26, 49, § 113: inter densas, umbrosa cacumina, fagos, Verg. E. 2, 3: Silae, Prop. 1, 20, 7; Ov. M. 1, 693: in umbrosis lucis, Hor. C. 1, 4, 11: nemus, Ov. M. 7, 75: salices, id. F. 3, 17: vallis, Verg. G. 3, 331: harundo, id. A. 8, 34: orae Heliconis, Hor. C. 1, 12, 5: arx Parnasi, Ov. M. 1, 467: Ida, id. ib. 11, 762: tecta, Tib. 1, 4, 1: cavernae, Verg. A. 8, 242: ripa, Hor. C. 3, 1, 23: templa, Ov. M. 11, 360.
Subst. plur.: umbrōsa, ōrum, n., the twilight, dim light (opp. tenebrae, clara lux), Sen. Ep. 94, 20.