I.a sketch in shadow, à la silhouette, a perspective sketch or draft (cf. adumbro).
I. Lit.: “scenographia est frontis et laterum abscedentium adumbratio,” Vitr. 1, 2.—
II. Fig., a sketch, outline: nulla est laus oratoris, cujus in nostris orationibus non sit aliqua, si non perfectio, at conatus tamen atque adumbratio, * Cic. Or. 29.—Hence,
B. A false show, the semblance of a thing, pretence: “insidiosa beneficii adumbratio,” Val. Max. 7, 3, 8; cf. Cic. Off. 1, 14, 44.