adumbrate
v.
"to outline, to sketch," 1580s, from Latin adumbratus "sketched, shadowed in outline," past participle of adumbrare "to represent (a thing) in outline" (see adumbration). Meaning "to overshadow" is 1660s. Related: Adumbrated; adumbrating.
〔李〕[ad-;umbr;-atev.] v.勾画； 暗示； 遮蔽 ←umbr (L umbra)=shade or shadow 阴影
〔蒋〕[ad-表示at，to，umbr影，-ate动词后缀;’画…的影”] 勾画，画…的轮廓，在…上投下阴影