1 [count] : a dark shape that appears on a surface when someone or something moves between the surface and a source of light
▪ The tree cast/threw a long shadow across the lawn. ▪ You can see your own shadow on a sunny day. — often used figuratively ▪ a town located in the shadow of the Rocky Mountains [=a town located very close to the Rocky Mountains] ▪ The bad news cast a shadow on the party. [=made the party much less enjoyable] ▪ His death left a shadow over her heart. ▪ For years they lived under the shadow of a dictator. [=they were ruled by a dictator] ▪ He couldn't escape his father's shadow. [=he couldn't escape the influence of his powerful/successful father] ▪ She grew up in the shadow of her very popular sister. [=people did not notice her because of all the attention that was given to her sister] 2 : an area of darkness created when a source of light is blocked [noncount] ▪ Part of the valley was in shadow. [plural] ▪ He saw something moving in the shadows. 3 [singular] : a very small amount of something
▪ I sensed a shadow of disappointment in his expression. ▪ There is not a shadow of (a) doubt [=there is no doubt] that he is lying. 4 [count] : someone who follows another person or who is always seen with another person
▪ He is the President's adviser and shadow. 5 [count] : a dark area of skin under a person's eyes — usually plural ▪ She woke up with dark shadows [=circles] under her eyes. 6 [count] : someone or something that is now much weaker, less impressive, etc., than in the past — + of ▪ The city today is just/only a shadow of what it once was. ▪ He was once a great player, but now he's just a shadow of his former self.