umbrella umbr=shadow 表示”影子”
A device for protection from the weather consisting of a collapsible, usually circular canopy mounted on a central rod.
Something that covers or protects. Air cover, especially during a military operation.
Something that encompasses or covers many different elements or groups.
Zoology. The gelatinous, rounded mass that is the major part of the body of most jellyfish.
n. 雨伞；保护伞；庇护；伞形结构

umbra
A dark area, especially the blackest part of a shadow from which all light is cut off. See Synonyms at shade.
Astronomy. The completely dark portion of the shadow cast by the earth, moon, or other body during an eclipse. The darkest region of a sunspot.
n. [天] 本影，[天] 暗影； (太阳黑子的)中央黑暗部

penumbra
A partial shadow, as in an eclipse, between regions of complete shadow and complete illumination. See Synonyms at shade.
The grayish outer part of a sunspot.
An area in which something exists to a lesser or uncertain degree
An outlying surrounding region; a periphery
n. 半影；浓淡相交之处；画面明暗交界处；程度较弱的周围；边缘；外围部分

例句：
“Downtown Chicago and its penumbra also stand rejuvenated”(&b{John McCormick})
“芝加哥城商业中心及其周边地区都恢复了生机”(约翰·麦考密克)

adumbrate
To give a sketchy outline of.
To prefigure indistinctly; foreshadow.
To disclose partially or guardedly.
To overshadow; shadow or obscure.
vt. 画…的轮廓；遮蔽，遮暗, 给...投下阴影；预示

例句：
The recent development adumbrate a world-wide revolution in computer technology.
最新事态的发展预示着一场全球性的计算机技术革命。

umbrage
Offense; resentment
Something that affords shade. Shadow or shade. See Synonyms at shade.
A vague or indistinct indication; a hint.
n.形成阴影的东西；模糊的或不明显的表示；不快，烦恼；触怒

sombre 美式somber sub+umbra

词汇起源
[Date: 1700-1800; Language: French; Origin: sombre, probably from Latin sub 'under' + umbra 'shade, shadow']

Dark; gloomy. Dull or dark in color.
Melancholy; dismal: a somber mood. Serious; grave.
adj. 忧郁的；昏暗的；严峻的；阴天的

例句：
He had a somber expression on his face.
他面容忧郁。
His expression was somber as he listened to the report of the accident.
他听着关于事故的报告时,脸部表情严峻。