Meaning

noun the act of providing vague advance indications; representing beforehand

noun a sketchy or imperfect or faint representation

originFrom Latin adumbrātiō (“sketch; outline, silhouette; pretence, semblance”) + -ion (suffix indicating a condition or state). Adumbrātiō is derived from adumbrāre (present active infinitive of adumbrō (“to represent an object with light and shade, to shade; to represent in outline, to outline, silhouette, sketch; to cast a shadow on, overshadow, shade; to copy, counterfeit, imitate”)) + -tiō…

Etymology from Wiktionary, CC BY-SA 3.0